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Lincoln Navigator: Automatic Transmission External Controls / External Controls. Diagnosis and Testing

Lincoln Navigator 2018-2025 Workshop Manual / Automatic Transmission / Automatic Transmission External Controls / External Controls. Diagnosis and Testing

Inspection and Verification

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

  1. Verify the customer concern.
  1. Visually inspect for obvious signs of mechanical or electrical damage.
  1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  1. If the cause is not visually evident, retrieve all GSM diagnostic trouble codes (DTCs) and refer to the DTC Chart.
  1. If no diagnostic trouble codes (DTCs) are present, verify the symptom and refer to the Global Customer Symptom Code (GCSC) Chart.

  Visual Inspection Chart


Mechanical Electrical
Gear select buttons Wiring harness
Paddle shift switches Park lock pawl solenoid
Transmission internal park components Connectors
  Paddle shifters

Diagnostic Trouble Code (DTC) Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


Module DTC Description Action
GSM P0562:00 System Voltage Low: No Sub Type Information GO to Pinpoint Test A
GSM P0563:00 System Voltage High: No Sub Type Information GO to Pinpoint Test B
GSM P0605:00 Internal Control Module Read Only Memory (ROM) Error: No Sub Type Information GO to Pinpoint Test H
GSM P0606:00 Control Module Processor: No Sub Type Information GO to Pinpoint Test H
GSM P0607:00 Control Module Performance: No Sub Type Information GO to Pinpoint Test H
GSM P06B8:00 Internal Control Module Non-Volatile Random Access Memory (NVRAM) Error: No Sub Type Information GO to Pinpoint Test H
GSM P07EC:00 Transmission Range Multi-Function Select Circuit: No Sub Type Information GO to Pinpoint Test C
GSM P07ED:00 Transmission Range Multi-Function Select Circuit Stuck: No Sub Type Information GO to Pinpoint Test C
GSM P0814:00 Transmission Range Display Circuit: No Sub Type Information GO to Pinpoint Test D
GSM P164E:00 Internal Control Module Transmission Range Select Performance: No Sub Type Information GO to Pinpoint Test H
GSM P166B:00 Drivers Door Status Correlation: No Sub Type Information GO to Pinpoint Test E
GSM U0100:00 Lost Communication With ECM/PCM 'A': No Sub Type Information GO to Pinpoint Test I
GSM U0100:87 Lost Communication With ECM/PCM 'A': Missing Message GO to Pinpoint Test I
GSM U0121:00 Lost Communication With Anti-Lock Brake System (ABS) Control Module 'A': No Sub Type Information GO to Pinpoint Test J
GSM U0140:00 Lost Communication With Body Control Module: No Sub Type Information GO to Pinpoint Test K
GSM U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information GO to Pinpoint Test L
GSM U0301:00 Software Incompatibility with ECM/PCM: No Sub Type Information GO to Pinpoint Test M
GSM U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information GO to Pinpoint Test I
GSM U0422:00 Invalid Data Received From Body Control Module: No Sub Type Information GO to Pinpoint Test K

Global Customer Symptom Code (GCSC) Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


Symptom Action
Start/Run/Move > Moving > Gear Selector > Inoperative GO to Pinpoint Test F
Start/Run/Move > Moving > Gear Selector > Inoperative GO to Pinpoint Test P
Start/Run/Move > Moving > Gear Selector > Sticks/Binds GO to Pinpoint Test Q
Start/Run/Move > Moving > Paddle/SelectShift > Inoperative GO to Pinpoint Test G
Start/Run/Move > Moving > Engagement Quality > Park GO to Pinpoint Test N
Start/Run/Move > Moving > Engagement Quality > Park GO to Pinpoint Test O

Pinpoint Tests


PINPOINT TEST A: DTC P0562

Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM requires an operating voltage between 9 and 16 volts. The GSM receives this voltage from the BCM and has dual ground circuits. Excessive resistance or an open in one or more of these circuits, a discharged battery or a inoperative charging system results in the GSM setting a DTC .

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM P0562:00 System Voltage Low: No Sub Type Information This DTC sets in continuous memory if the voltage supplied to the GSM falls below 9 volts for more than 3 seconds.

Possible Sources

  • Battery or charging system concern
  • BCM fuse F7
  • Wiring, terminals or connectors
  • GSM

Visual Inspection and Pre-checks

  • Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
  • Make sure the vehicle battery terminals are tightened to their correct torque specifications.
  • Make sure BCM fuse F7 is OK.
A1 RECHECK THE GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, clear all GSM diagnostic trouble codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC P0562 still present?
Yes GO to A2
No The system is operating correctly at this time. The DTC may have set due to a previous low battery voltage condition.

A2 CHECK FOR CHARGING SYSTEM DIAGNOSTIC TROUBLE CODES (DTCS) IN THE PCM (POWERTRAIN CONTROL MODULE)
  • Using a diagnostic scan tool, retrieve all continuous memory diagnostic trouble codes (CMDTCs).

Are any charging system Diagnostic Trouble Codes (DTCs) present in the PCM ?
Yes DIAGNOSE the vehicle charging concern.
REFER to: Charging System - 3.5L EcoBoost (272kW/370PS) (414-00 Charging System - General Information, Diagnosis and Testing).
No GO to A3

A3 CHECK THE BATTERY CONDITION AND STATE OF CHARGE
  • Carry out the Battery Condition Test.
    REFER to: Battery (414-01 Battery, Mounting and Cables, Diagnosis and Testing).

Did the battery pass the condition test?
Yes GO to A4
No INSTALL a new battery.
REFER to: Battery (414-01 Battery, Mounting and Cables, Removal and Installation).

A4 CHECK THE GSM (GEAR SHIFT MODULE) VOLTAGE SUPPLY
  • Ignition OFF.
  • Disconnect GSM C2532.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-1   Ground

Is the voltage within 1 volt of the recorded battery voltage?
Yes GO to A5
No VERIFY BCM fuse F7 is OK.
If the fuse is OK, REFER to the Wiring Diagrams manual to identify and repair an open circuit
If the fuse is not OK, REFER to the Wiring Diagrams manual to identify and repair a short to ground.

A5 CHECK THE GSM (GEAR SHIFT MODULE) GROUND CIRCUIT FOR AN OPEN
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-9   Ground

Are the resistances less than 3 ohms?
Yes GO to A6
No Verify ground G200 is clean and properly fastened. If OK, REPAIR the circuit.

A6 VERIFY ALL WIRING CONNECTIONS
  • Ignition OFF.
  • Disconnect and inspect GSM C2532 and related in-line electrical connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary

Are the connectors free of corrosion, damaged pins, bent pins, pushed-out pins and spread terminals?
Yes GO to A7
No REPAIR the connector, terminals as necessary.

A7 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Connect GSM C2532 and all related in-line electrical connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST B: DTC P0563

Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM requires an operating voltage between 9 and 16 volts. The GSM receives this voltage from the BCM and has dual ground circuits. Excessive resistance or an open in one or more of these circuits, a discharged battery or a inoperative charging system or overcharging condition results in the GSM setting a DTC . This DTC may also set in the GSM module due to battery charging or vehicle jump starting events.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM P0563:00 System Voltage High: No Sub Type Information This DTC sets in continuous memory if the voltage supplied to the GSM module is above 16 volts for more than 3 seconds.

Possible Sources

  • Charging system concern
  • GSM module
B1 CHECK FOR CHARGING SYSTEM DIAGNOSTIC TROUBLE CODES (DTCS) IN THE PCM (POWERTRAIN CONTROL MODULE)
  • Using a diagnostic scan tool, retrieve all continuous memory diagnostic trouble codes (CMDTCs).

Are any charging system diagnostic trouble codes (DTCs) present in the PCM ?
Yes DIAGNOSE the vehicle charging concern.
REFER to: Charging System - 3.5L EcoBoost (272kW/370PS) (414-00 Charging System - General Information, Diagnosis and Testing).
No GO to B2

B2 CHECK THE BATTERY VOLTAGE
  • Using a diagnostic scan tool, clear all GSM diagnostic trouble codes (DTCs).
  • Turn off all interior lights, exterior lights and accessories.
  • NOTE: Do not allow the engine speed to increase above 2,000 RPM while performing this step or the generator may self-excite and result in default charging system output voltage. If engine speed goes above 2,000 RPM , turn the engine off and restart the engine before performing this step. Start and run the engine at approximately 1,500 RPM for 3 minutes while monitoring the battery voltage.

Does the battery voltage stay between 13 and 15.2 volts?
Yes GO to B3
No DIAGNOSE the overcharging condition.
REFER to: Charging System - 3.5L EcoBoost (272kW/370PS) (414-00 Charging System - General Information, Diagnosis and Testing).

B3 RECHECK THE GSM (GEAR SHIFT MODULE) FOR DTC (DIAGNOSTIC TROUBLE CODE) P0563

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC P0563 still present?
Yes GO to B4
No The system is operating normally at this time. The DTC may have been set previously during battery charging or while jump starting the vehicle.

B4 VERIFY ALL WIRING CONNECTIONS
  • Ignition OFF.
  • Disconnect and inspect GSM C2532 and related in-line electrical connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary

Are the connectors free of corrosion, damaged pins, bent pins, pushed-out pins and spread terminals?
Yes GO to B5
No REPAIR as necessary.

B5 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Connect GSM C2532 and all related in-line electrical connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST C: DTC P07EC, P07ED

Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM contains 3 electrical contacts beneath each gear select button. If 1 contact does not switch properly with the other 2 contacts, or if all 3 contacts have been closed for 30 seconds, indicating a stuck button, a DTC will set.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM P07EC:00 Transmission Range Multi-Function Select Circuit: No Sub Type Information This DTC sets in continuous memory if one of the contacts in a gear select button does not match the other 2.
GSM P07ED:00 Transmission Range Multi-Function Select Circuit Stuck: No Sub Type Information This DTC sets if one of the gear select buttons have been closed for 30 seconds or more.

Possible Sources

  • Connectors damaged or pushed-out terminals, circuitry open, shorted to power or shorted to ground
  • GSM
C1 INSPECT THE GEAR SELECT BUTTONS
  • Inspect the GSM gear select buttons for debris or foreign material that could cause them to stick.
  • Press and release the GSM gear select buttons. Make sure they all move freely.

Are the GSM gear select buttons free of debris and foreign material, and do all move freely?
Yes GO to C2
No Clean any debris or foreign material from the switches. GO to C2
If any of the GSM gear select buttons still stick after cleaning it, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).

C2 CHECK THE GEAR SELECT BUTTONS AND BTSI OVERRIDE SWITCH PID STATUS
  • Using a diagnostic scan tool, access the GSM and monitor the following parameter identifications (PIDs):
    • P button, SBW_PRK_SW_1, SBW_PRK_SW_2, SBW_PRK_SW_3
    • R button, SBW_REV_SW_1, SBW_REV_SW_2, SBW_REV_SW_3
    • N button, SBW_NEU_SW_1, SBW_NEU_SW_2, SBW_NEU_SW_3
    • D button, SBW_DRV_SW_1, SBW_DRV_SW_2, SBW_DRV_SW_3
  • Do not press any of the buttons.

Do any of the switch PID readings indicate that a GSM gear select button is pressed?
Yes If one of the GSM gear select button parameter identifications (PIDs) indicates a button is pressed, GO to C5
No GO to C3

C3 CHECK THE OPERATION OF THE GEAR SELECT BUTTONS
  • Using a diagnostic scan tool, access the GSM and monitor the following parameter identifications (PIDs):
    • P button, SBW_PRK_SW_1, SBW_PRK_SW_2, SBW_PRK_SW_3
    • R button, SBW_REV_SW_1, SBW_REV_SW_2, SBW_REV_SW_3
    • N button, SBW_NEU_SW_1, SBW_NEU_SW_2, SBW_NEU_SW_3
    • D button, SBW_DRV_SW_1, SBW_DRV_SW_2, SBW_DRV_SW_3
  • While observing the gear select button parameter identifications (PIDs), press and release each button several times.

Do all the PID readings change correctly as the gear select buttons are pressed and released?
Yes GO to C4
No If one or more of the gear select button parameter identifications (PIDs) do not change correctly, GO to C5

C4 RECHECK THE GSM (GEAR SHIFT MODULE) FOR DTCS

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using the diagnostic scan tool, clear all GSM diagnostic trouble codes (DTCs)
  • Ignition OFF.
  • Ignition ON.
  • Wait 2 minutes.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC P07EC or P07ED present?
Yes GO to C5
No The system is operating correctly at this time. The concern may have been caused by debris or interference around one of the switches.

C5 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Using a diagnostic scan tool, clear all GSM diagnostic trouble codes (DTCs).
  • Ignition OFF.
  • Disconnect and inspect GSM C2532.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect GSM C2532. Make sure it seats and latches correctly.
  • Operate the system and verify the concern is still present

Is the concern still present?
Yes CHECK OASIS for any applicable TSB s. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSB s address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST D: DTC P0814

Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM monitors the gear select buttons, and the illumination of each gear indicator LED .

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM P0814:00 Transmission Range Display Circuit: No Sub Type Information This DTC sets if the GSM detects the wrong gear selection LED is illuminated.

Possible Sources

  • Connectors damaged or pushed-out terminals, circuitry open or high resistance in the voltage feed wiring to the GSM or a loose ground.
  • Discharged battery/charging system
  • GSM
D1 VERIFY THE BATTERY IS FULLY CHARGED
  • NOTE: If necessary, connect the battery charger to the vehicle battery to insure a steady battery voltage while performing this test. VERIFY battery is fully charged before proceeding with this test.
    REFER to: Battery (414-01 Battery, Mounting and Cables, Diagnosis and Testing).

Is the battery fully charged?
Yes GO to D2
No CHARGE or INSTALL a new battery if necessary.
REFER to: Battery (414-01 Battery, Mounting and Cables, Removal and Installation).

D2 CHECK GSM CALIBRATION LEVEL
  • VERIFY the GSM calibration is at the latest level.

Is the GSM calibration at the latest level?
Yes GO to D3
No PROGRAM the GSM with the latest calibration.
REFER to: Module Programming (418-01A Module Configuration, General Procedures).

D3 CHECK THE GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, clear all GSM diagnostic trouble codes (DTCs).
  • Ignition OFF.
  • Wait 10 seconds.
  • Start the engine.
  • Press each gear select button, pausing after each one.
  • Select PARK.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC P0814 or P0915 still present?
Yes If DTC P0562 or P0563 is also present, RESOLVE those diagnostic trouble codes (DTCs) first.
Otherwise, GO to D4
No The fault is not present at this time and might be intermittent.

D4 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect GSM C2532.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect GSM C2532. Make sure it seats and latches correctly.
  • Operate the system and verify the concern is still present

Is the concern still present?
Yes CHECK OASIS for any applicable TSB s. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSB s address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST E: AUTOMATIC RETURN TO PARK FUNCTION DOES NOT OPERATE CORRECTLY

Refer to Wiring Diagrams Cell 117 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM uses the drivers door unlock switch input and drivers door status input to shift the transmission into the park position when the operator is preparing to exit the vehicle.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM P166B:00 Drivers Door Status Correlation: No Sub Type Information The GSM monitors the voltage signals on the door status and door unlock switch inputs. If these inputs fail a rational test between them, the DTC sets.

Possible Sources

  • Connectors damaged or pushed-out terminals, circuitry open, shorted to power or shorted to ground
  • Driver door ajar switch
  • Driver door lock/unlock switch
  • GSM
E1 CHECK THE OPERATION OF THE DOOR LOCKS AND LATCHES
  • Open and close the driver door while observing the door ajar icon on the IPC .
  • Lock and unlock the doors using the driver door unlock switch. Verify the locks operate properly.

Does the door ajar icon on the IPC toggle on and off as the driver door is opened and closed, and do the door locks function properly.
Yes GO to E2
No RESOLVE the door lock and/or latch concern first.
REFER to: Locks, Latches and Entry Systems (501-14 Handles, Locks, Latches and Entry Systems, Diagnosis and Testing).

E2 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, carry out the GSM self-test and retrieve all diagnostic trouble codes (DTCs).

Is DTC P166B present?
Yes GO to E3
No If any symptoms related to the automatic return to park function are present, GO to E3
If there are no observable symptoms, the concern is not present at this time. The DTC might have been set by carrying out a GSM self-test without the door being fully closed and locked.

E3 MONITOR THE DOOR UNLOCK PID
  • Using a diagnostic scan tool, access the GSM and monitor PID DR_UNLCK_HWI while pressing and releasing the driver door unlock switch.

Does the PID toggle appropriately while pressing and releasing the driver door unlock switch?
Yes GO to E6
No GO to E4

E4 CHECK THE DOOR UNLOCK CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect GSM C2532 .
  • Disconnect Front Door Latch LH C525A .
  • Disconnect Interior Front Door Handle Ambient Lighting Lamp LH C5018 .
  • Inspect the connectors for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-4   C525A-4

Is the resistance less than 3 ohms?
Yes GO to E5
No REPAIR the circuit.

E5 CHECK THE DOOR UNLOCK CIRCUIT FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-4   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to E9
No REPAIR the circuit.

E6 MONITOR THE DOOR AJAR PID
  • Using the diagnostic scan tool, access the GSM and monitor PID , DOOR_AJAR_HWI while opening and closing the driver door.

Does the PID toggle appropriately as the driver door is opened and closed?
Yes GO to E9
No GO to E7

E7 CHECK THE DOOR AJAR CIRCUIT FOR AN OPEN
  • Disconnect GSM C2532 .
  • Disconnect BCM C2280E .
  • Disconnect Front Door Latch LH C525A .
  • Inspect the connectors for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-15   C525A-6

Is the resistance less than 3 ohms?
Yes GO to E8
No REPAIR the circuit.

E8 CHECK THE DOOR AJAR CIRCUIT FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-15   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to E9
No REPAIR the circuit.

E9 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Ignition OFF.
  • Disconnect and inspect GSM C2532.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect GSM C2532 and all other connectors that are currently disconnected. Make sure they seat and latch correctly.
  • Operate the system and verify the concern is still present

Is the concern still present?
Yes CHECK OASIS for any applicable TSB s. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSB s address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST F: PROGRESSIVE RANGE SELECTION DOES NOT OPERATE CORRECTLY

Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

When the gear shift is in (D) position and the vehicle is not moving, with either the plus (+) or minus (-) switch pulled, the IPC displays all available gear positions 1st, 2nd, 3rd, 4th, 5th, and 6th, through 10 are displayed with 1st gear highlighted. If the plus (+) switch is then pressed, the available gear positions are no longer displayed, until either the plus (+) or minus (-) switch is pressed again. The paddle, + and - switches are used for the progressive range selection are shared with the Selectshift™ system.

Possible Sources

  • Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
  • Paddle shift switch
  • PCM
F1 CHECK THE COMMUNICATION NETWORK
  • Ignition ON.
  • Using the diagnostic scan tool, perform the network test.

Do the PCM , GSM and IPC pass the network test?
Yes GO to F2
No To diagnose a module does not respond to the scan tool,
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

F2 CHECK THE PADDLE SHIFT SYSTEM
  • Ignition ON.
  • Road test the vehicle.
  • Operate the paddle shift system to upshift and downshift the transmission.

Does the paddle shift system operate correctly?
Yes If the symptom is still present, RESOLVE any network and non-network diagnostic trouble codes (DTCs) in the PCM and IPC .
No GO to Pinpoint Test G

PINPOINT TEST G: PADDLE SHIFTERS ARE INOPERATIVE OR DO NOT OPERATE PROPERLY

Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

The paddle shift switches are integral to the steering wheel. The upshift/downshift feature becomes activated when the driver pulls the + paddle on the steering wheel. This feature allows the driver to upshift and downshift without removing their hands from the steering wheel. If a new switch is required, install a new paddle shift assembly.

Possible Sources

  • Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
  • Paddle shift switch
  • PCM
G1 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, carry out the GSM self-test.

Are any GSM diagnostic trouble codes (DTCs) present?
Yes RESOLVE all GSM diagnostic trouble codes (DTCs) first.
No GO to G2

G2 CHECK THE UPSHIFT AND DOWNSHIFT INPUTS TO THE PCM (POWERTRAIN CONTROL MODULE)
  • Using a diagnostic scan tool, access the PCM and monitor PID SST_U and SST_D.
  • Press and release the upshift paddle switch while observing PID SST_U.
  • Press and release the downshift paddle switch while observing PID SST_D.

Does each PID agree with the corresponding switch as the switch is pressed and released?
Yes GO to G3
No GO to G4

G3 CHECK THE OPERATION OF THE PADDLE SHIFT SYSTEM
  • Road test the vehicle and use the paddle shifters to upshift and downshift the transmission.

Do the paddle shifters operate properly?
Yes The paddle shift system is working properly at this time. INSPECT harness connectors for loose terminals or corrosion that could cause an intermittent fault.
No If any diagnostic trouble codes (DTCs) related to the transmission are present in the PCM or the GSM , RESOLVE those first.
If no diagnostic trouble codes (DTCs) related to the transmission are present and the paddle shift switch concern continues,
   Click here to access Guided Routine (PCM)..
After installing a new PCM , CARRY OUT the transmission strategy download.
REFER to: Transmission Strategy Download (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, General Procedures).

G4 CHECK THE UPSHIFT PADDLE SWITCH
  • Ignition OFF.
  • Disconnect Upshift paddle switch C2428 .
  • Inspect the connector for damaged or pushed-out terminals.
  • Measure the following while pressing and releasing the upshift paddle switch:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    Upshift paddle switch, component side, Pin 2 Upshift paddle switch, component side, Pin 3

Is the resistance less than 1.5 ohms with the upshift paddle switch pressed and greater than 10,000 ohms with the switch released?
Yes GO to G5
No INSTALL a new upshift paddle switch.
REFER to: Upshift Paddle Switch (307-05 Automatic Transmission External Controls, Removal and Installation).

G5 CHECK THE UPSHIFT SIGNAL CIRCUIT FOR VOLTAGE
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2428-2   Ground

Is the voltage greater than 11 volts?
Yes GO to G8
No GO to G6

G6 CHECK THE UPSHIFT SIGNAL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect PCM C175T .
  • Inspect the connector for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C175T-57   C2428-2

Is the resistance less than 3 ohms?
Yes GO to G7
No REFER to the Wiring Diagrams manual to identify and repair the open circuit.

G7 CHECK THE UPSHIFT SIGNAL CIRCUIT FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C175T-57   Ground

Is the resistance greater than 10,000 ohms?
Yes
   Click here to access Guided Routine (PCM).
After installing a new PCM , CARRY OUT the transmission strategy download.
REFER to: Transmission Strategy Download (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, General Procedures).
No REFER to the Wiring Diagrams manual to identify and repair the short to ground.

G8 CHECK THE DOWNSHIFT PADDLE SWITCH
  • Ignition OFF.
  • Disconnect Downshift paddle switch C2429 .
  • Inspect the connector for damaged or pushed-out terminals.
  • Measure the following while pressing and releasing the downshift paddle switch:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    Downshift paddle switch, component side, Pin 2 Downshift paddle switch, component side, Pin 3

Is the resistance less than 1.5 ohms with the downshift paddle switch pressed and greater than 10,000 ohms with the switch released?
Yes GO to G9
No INSTALL a new downshift paddle switch.
REFER to: Downshift Paddle Switch (307-05 Automatic Transmission External Controls, Removal and Installation).

G9 CHECK THE DOWNSHIFT SIGNAL CIRCUIT FOR VOLTAGE
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2429-2   Ground

Is the voltage greater than 11 volts?
Yes GO to G12
No GO to G10

G10 CHECK THE DOWNSHIFT SIGNAL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect PCM C175T .
  • Inspect the connector for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C175T-42   C2429-2

Is the resistance less than 3 ohms?
Yes GO to G11
No REFER to the Wiring Diagrams manual to identify and repair the open circuit.

G11 CHECK THE DOWNSHIFT SIGNAL CIRCUIT FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C175T-42   Ground

Is the resistance greater than 10,000 ohms?
Yes
   Click here to access Guided Routine (PCM).
After installing a new PCM , CARRY OUT the transmission strategy download.
REFER to: Transmission Strategy Download (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, General Procedures).
No REFER to the Wiring Diagrams manual to identify and repair the short to ground.

G12 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect PCM C175T .
  • Disconnect Upshift paddle switch C2428 (if not already disconnected).
  • Disconnect Downshift paddle switch C2429 (if not already disconnected).
  • Inspect the connectors for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C175T-19   C2428-3
      C175T-19   C2429-3

Are the resistances less than 3 ohms?
Yes GO to G13
No REFER to the Wiring Diagrams manual to identify and repair an open circuit.

G13 CHECK THE SIGNAL RETURN CIRCUIT FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C175T-19   Ground

Is the resistance greater than 10,000 ohms?
Yes
   Click here to access Guided Routine (PCM).
After installing a new PCM , CARRY OUT the transmission strategy download.
REFER to: Transmission Strategy Download (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, General Procedures).
No REFER to the Wiring Diagrams manual to identify and repair a short to ground.

PINPOINT TEST H: INTERNAL MODULE DTCS

Normal Operation and Fault Conditions

The GSM performs periodic tests on itself. It sets a DTC if any of the results are outside of normal operating standards.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM P0605:00 Internal Control Module Read Only Memory (ROM) Error: No Sub Type Information The GSM detected a ROM checksum error.
GSM P0606:00 Control Module Processor: No Sub Type Information The GSM detected a reset without going through a proper sleep cycle.
GSM P0607:00 Control Module Performance: No Sub Type Information The GSM detected an early or delayed response of greater than 10 percent of its periodic rate.
GSM P06B8:00 Internal Control Module Non-Volatile Random Access Memory (NVRAM) Error: No Sub Type Information The GSM detected a RAM checksum error.
GSM P164E:00 Internal Control Module Transmission Range Select Performance: No Sub Type Information The GSM detected a start up test failure, a program flow monitor failure, an IPC software failure, or a 5V_1_MONITOR failure.

Possible Sources

  • Discharged battery/charging system
  • GSM calibration
  • GSM
H1 CHECK THE GSM (GEAR SHIFT MODULE) FOR CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODES (CMDTCS)
  • Ignition ON.
  • Retrieve all continuous memory diagnostic trouble codes (CMDTCs) from the GSM .

Is DTC P0562 or P0563 present in the GSM ?
Yes RESOLVE those diagnostic trouble codes (DTCs) first.
No GO to H2

H2 PROGRAM THE GSM (GEAR SHIFT MODULE) WITH THE LATEST CALIBRATION

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Ignition ON.
  • Clear all diagnostic trouble codes (DTCs) from the GSM .
  • Reprogram the GSM with the latest calibration.
    REFER to: Module Programming (418-01A Module Configuration, General Procedures).
  • Road test the vehicle.
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC P0605, P0606, P0607, P06B8 or P164E present in the GSM ?
Yes INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The fault is not present at this time. It may have been caused by a module programming error.

PINPOINT TEST I: DTC U0100, U0401

Refer to Wiring Diagrams Cell 14 for schematic and connector information. Refer to Wiring Diagrams Cell 29 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM and PCM communicate over HS-CAN1 and HS-CAN2 through the GWM . They also communicate over a dedicated Transmission CAN .

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM U0100:00 Lost Communication With ECM/PCM 'A': No Sub Type Information This DTC sets if the GSM does not receive some or all of an expected message from the PCM over HS-CAN2 .
GSM U0100:87 Lost Communication With ECM/PCM 'A': Missing Message This DTC sets if the GSM does not receive some or all of an expected message from the PCM over CAN .
GSM U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information This DTC sets if the GSM detects invalid data from the PCM .

Possible Sources

  • Communication concern
  • PCM
  • GSM
I1 VERIFY THE SCAN TOOL COMMUNICATES WITH THE PCM (POWERTRAIN CONTROL MODULE)
  • Using a diagnostic scan tool, carry out the PCM self-test.

Did the PCM complete the self-test?
Yes GO to I2
No To diagnose the module does not respond to the scan tool,
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

I2 RETRIEVE THE DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE PCM (POWERTRAIN CONTROL MODULE)
  • Using a diagnostic scan tool, retrieve all diagnostic trouble codes from the PCM self-test.

Are any non-network diagnostic trouble codes (DTCs) present in the PCM ?
Yes RESOLVE those DTC s first.
REFER to: Electronic Engine Controls (303-14 Electronic Engine Controls - 3.5L EcoBoost (272kW/370PS), Diagnosis and Testing).
No GO to I3

I3 CHECK FOR GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, carry out the GSM self-test.

Are any non-network GSM diagnostic trouble codes (DTCs) present?
Yes RESOLVE all non-network diagnostic trouble codes (DTCs) first. REFER to the GSM DTC chart.
No GO to I4

I4 CHECK FOR GWM (GATEWAY MODULE A) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, carry out the GWM self-test.

Are any diagnostic trouble codes (DTCs) present in the GWM ?
Yes RESOLVE all GWM diagnostic trouble codes (DTCs) first.
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).
No GO to I5

I5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0100, U0401 SET IN OTHER MODULES
  • Using a diagnostic scan tool, retrieve all continuous memory diagnostic trouble codes (CMDTCs) from all modules.

Is DTC U0100 and/or U0401 present in other modules?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern,
   Click here to access Guided Routine (PCM).
After installing a new PCM , CARRY OUT the transmission strategy download.
REFER to: Transmission Strategy Download (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, General Procedures).
No GO to I6

I6 PROGRAM THE PCM (POWERTRAIN CONTROL MODULE) WITH THE LATEST CALIBRATION

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, clear all diagnostic trouble codes (DTCs).
  • Program the PCM with the latest calibration.
  • Road test the vehicle.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC U0100, U0100:87 and/or U0401 still present?
Yes For DTC U0100:00 and/or U0401, GO to I7
For DTC U0100:87, GO to I9
No The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

I7 CHECK THE HS-CAN2 (HIGH-SPEED CONTROLLER AREA NETWORK 2) CIRCUITS FOR AN OPEN
  • Ignition OFF.
  • Disconnect GSM C2532 .
  • Disconnect PCM C1915B .
  • Disconnect GWM C4391A .
  • Inspect the connectors for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-2   C4391A-21
      C2532-3   C4391A-8
      C175B-33   C4391A-17
      C175B-48   C4391A-4

Are the resistances less than 3 ohms?
Yes GO to I8
No REPAIR the circuit.

I8 CHECK THE HS-CAN2 (HIGH-SPEED CONTROLLER AREA NETWORK 2) CIRCUITS FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4391A-4   Ground
      C4391A-8   Ground
      C4391A-17   Ground
      C4391A-21   Ground

Are the resistances greater than 10,000 ohms?
Yes GO to I11
No REPAIR the circuit.

I9 CHECK THE TRANS CAN (CONTROLLER AREA NETWORK) CIRCUITS FOR AN OPEN
  • Ignition OFF.
  • Disconnect GSM C2532 .
  • Disconnect PCM C175T .
  • Inspect the connectors for damaged or pushed-out terminals.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-13   C175T-8
      C2532-14   C175T-23

Are the resistances less than 3 ohms?
Yes GO to I10
No REPAIR the circuit.

I10 CHECK THE TRANS CAN (CONTROLLER AREA NETWORK) CIRCUITS FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2532-13   Ground
      C2532-14   Ground

Are the resistances greater than 10,000 ohms?
Yes GO to I11
No REPAIR the circuit.

I11 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect GSM C2532 and all related in-line electrical connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary
  • Reconnect GSM C2532 and all related in-line electrical connectors. Make sure they seat and latch correctly.
  • Using the diagnostic scan tool, clear all DTC s.
  • Carry out the GSM self-test.

Are diagnostic trouble codes (DTCs) U0100 and/or U0401 still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST J: DTC U0121

Refer to Wiring Diagrams Cell 14 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM and ABS module use information contained in messages on the HS-CAN2 .

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM U0121:00 Lost Communication With Anti-Lock Brake System (ABS) Control Module 'A': No Sub Type Information Sets in continuous memory in the GSM if data messages received from the ABS are missing for 5 seconds or longer.

Possible Sources

  • Communication concern
  • ABS
  • GSM
J1 VERIFY THE SCAN TOOL COMMUNICATES WITH THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE
  • Using a diagnostic scan tool, carry out the ABS module self-test.

Did the ABS module complete the self-test?
Yes GO to J2
No To diagnose an ABS module does not communicate with the scan tool concern,
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

J2 RETRIEVE ALL ABS (ANTI-LOCK BRAKE SYSTEM) MODULE DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, retrieve all diagnostic trouble codes (DTCs) from the ABS self-test.

Are any non-network diagnostic trouble codes (DTCs) present?
Yes DIAGNOSE all non-network diagnostic trouble codes (DTCs) first.
REFER to: Anti-Lock Brake System (ABS) and Stability Control (206-09 Anti-Lock Brake System (ABS) and Stability Control, Diagnosis and Testing).
No GO to J3

J3 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, carry out the GSM self-test.

Are any non-network diagnostic trouble codes (DTCs) present?
Yes DIAGNOSE all non-network diagnostic trouble codes (DTCs) first. REFER to the GSM DTC Chart.
No GO to J4

J4 CHECK THE GWM (GATEWAY MODULE A) FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, check the GWM Continuous Memory Diagnostic Trouble Codes (CMDTCs).

Are any GWM diagnostic trouble codes (DTCs) present?
Yes
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).
No GO to J5

J5 RECHECK THE GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, clear the GSM diagnostic trouble codes (DTCs).
  • Road test the vehicle.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC U0121 still present?
Yes GO to J6
No The system is operating correctly at this time. The DTC may have set due to high network traffic or an intermittent fault condition.

J6 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0121 SET IN OTHER MODULES
  • Using the diagnostic scan tool, perform the self-test for all modules.
  • Retrieve the diagnostic trouble codes (DTCs) from all modules.

Is DTC U0121 present in other modules?
Yes GO to J7
No GO to J9

J7 CHECK FOR OTHER CAUSES OF NETWORK COMMUNICATION CONCERNS

NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

  • CHECK the vehicle service history for recent service actions related to the ABS . If recent service history is found:
    • verify correct replacement module was installed
      • HVBOM may be used to verify correct part application
    • verify the configuration of replacement module was correct
      • re-configure module using as-built data if prior configuration is suspect
    • verify the module was not obtained from a like vehicle and installed into customer vehicle
      • return the swapped module to source vehicle and obtain new replacement module
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes GO to J8
No The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

J8 CHECK FOR CORRECT ABS (ANTI-LOCK BRAKE SYSTEM) MODULE OPERATION
  • Ignition OFF.
  • Disconnect and inspect the ABS module and related in-line connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Reconnect the ABS module and all related in-line connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new electric brake booster.
REFER to: Electric Brake Booster (EBB) (206-09 Anti-Lock Brake System (ABS) and Stability Control, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

J9 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect GSM C2532 and all related in-line electrical connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary
  • Reconnect GSM C2532 and all related in-line electrical connectors. Make sure they seat and latch correctly.
  • Using the diagnostic scan tool, clear all DTC s.
  • Carry out the GSM self-test.

Is DTC U0121 still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST K: DTC U0140, U0422

Refer to Wiring Diagrams Cell 14 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM and BCM use information contained in HS-CAN messages.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM U0140:00 Lost Communication With Body Control Module: No Sub Type Information This DTC sets in continuous memory in the GSM if data messages received from the BCM are missing for 5 seconds or longer.
GSM U0422:00 Invalid Data Received From Body Control Module: No Sub Type Information This DTC sets if the GSM detects invalid data from the BCM .

Possible Sources

  • Communication concern
  • GSM
  • BCM
K1 VERIFY THE SCAN TOOL COMMUNICATES WITH THE BCM (BODY CONTROL MODULE)
  • Connect the diagnostic scan tool.
  • Check that a vehicle session can be established using the scan tool.

Can a vehicle session be established?
Yes GO to K2
No To diagnose a BCM does not communicate with the scan tool concern,
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

K2 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, carry out the GSM self-test.

Are any non-network diagnostic trouble codes (DTCs) present?
Yes RESOLVE all non-network diagnostic trouble codes (DTCs) first. REFER to the GSM DTC chart.
No GO to K3

K3 CHECK THE BCM (BODY CONTROL MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, carry out the BCM self-test.

Are any non-network diagnostic trouble codes (DTCs) present?
Yes RESOLVE all non-network diagnostic trouble codes (DTCs) first.
REFER to: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).
No GO to K4

K4 CHECK THE GWM (GATEWAY MODULE A) FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, carry out the GWM self-test.

Are any diagnostic trouble codes (DTCs) present?
Yes
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).
No GO to K5

K5 RECHECK THE GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, clear the GSM diagnostic trouble codes (DTCs).
  • Road test the vehicle.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC U0140 and/or U0422 still present?
Yes GO to K7
No The system is operating correctly at this time. The DTC may have set due to high network traffic or an intermittent fault condition.

K6 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0140, U0422 SET IN OTHER MODULES
  • Using the diagnostic scan tool, perform the self-test for all modules.
  • Retrieve the diagnostic trouble codes (DTCs) from all modules.

Is DTC U0140 and/or U0422 present in other modules?
Yes GO to K7
No GO to K9

K7 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERNS

NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

  • CHECK the vehicle service history for recent service actions related to the BCM or GSM . If recent service history is found:
    • verify correct replacement module was installed
      • HVBOM may be used to verify correct part application
    • verify the configuration of replacement module was correct
      • re-configure module using as-built data if prior configuration is suspect
    • verify the module was not obtained from a like vehicle and installed into customer vehicle
      • return the swapped module to source vehicle and obtain new replacement module
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes GO to K8
No The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

K8 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect the BCM and all related in-line connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary
  • Reconnect the BCM and all related in-line connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new BCM
REFER to: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
.
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

K9 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect GSM C2532 and all related in-line electrical connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary
  • Reconnect GSM C2532 and all related in-line electrical connectors. Make sure they seat and latch correctly.
  • Using the diagnostic scan tool, clear all diagnostic trouble codes (DTCs).
  • Carry out the GSM self-test.

Is DTC U0140 and/or U0422 still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST L: DTC U0155

Refer to Wiring Diagrams Cell 14 for schematic and connector information.

Normal Operation and Fault Conditions

The IPC , GSM and BCM use information contained in messages on the HS-CAN .

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information This DTC sets if the GSM does not receive some or all of an expected message from the IPC .

Possible Sources

  • Communication concern
  • GSM
  • IPC
L1 VERIFY THE SCAN TOOL COMMUNICATES WITH THE IPC (INSTRUMENT PANEL CLUSTER)
  • Using a diagnostic scan tool, carry out the IPC self-test.

Did the IPC complete the self-test?
Yes GO to L2
No To diagnose the IPC does not respond to the scan tool,
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).
REFER to: Controller Area Network (CAN) Module Communications Network - System Operation and Component Description (418-00A Controller Area Network (CAN) Module Communications Network, Description and Operation).

L2 RETRIEVE THE RECORDED DIAGNOSTIC TROUBLE CODES (DTCS) FROM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST
  • Check for DTC s from the self-test.

Are any non-network diagnostic trouble codes (DTCs) present?
Yes Diagnose those diagnostic trouble codes (DTCs) first.
REFER to: Instrumentation, Message Center and Warning Chimes (413-01 Instrumentation, Message Center and Warning Chimes, Diagnosis and Testing).
REFER to: Instrumentation, Message Center and Warning Chimes - Vehicles With: Head Up Display (HUD) (413-01 Instrumentation, Message Center and Warning Chimes, Diagnosis and Testing).
No GO to L3

L3 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using the diagnostic scan tool, carry out the GSM self-test.

Are any non-network diagnostic trouble codes (DTCs) present?
Yes RESOLVE those diagnostic trouble codes (DTCs) first. REFER to the GSM DTC Chart.
No GO to L4

L4 CHECK THE GWM (GATEWAY MODULE A) FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, carry out the GWM self-test.

Are any diagnostic trouble codes (DTCs) present?
Yes
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).
No GO to L5

L5 RECHECK THE GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed and locked. A false P166B DTC may set if the driver door is not fully closed and locked.

  • Using a diagnostic scan tool, clear the GSM diagnostic trouble codes (DTCs).
  • Road test the vehicle.
  • Using a diagnostic scan tool, carry out the GSM self-test.

Is DTC U0155 still present?
Yes GO to L6
No The system is operating correctly at this time. The DTC may have set due to high network traffic or an intermittent fault condition.

L6 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0155 SET IN OTHER MODULES
  • Using the diagnostic scan tool, perform the self-test for all modules.
  • Retrieve the diagnostic trouble codes (DTCs) from all modules.

Is DTC U0155 present in other modules?
Yes GO to L7
No GO to L9

L7 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERNS

NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

  • CHECK the vehicle service history for recent service actions related to the IPC or GSM . If recent service history is found:
    • verify correct replacement module was installed
      • HVBOM may be used to verify correct part application
    • verify the configuration of replacement module was correct
      • re-configure module using as-built data if prior configuration is suspect
    • verify the module was not obtained from a like vehicle and installed into customer vehicle
      • return the swapped module to source vehicle and obtain new replacement module
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes GO to L8
No The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

L8 CHECK FOR CORRECT IPC (INSTRUMENT PANEL CLUSTER) OPERATION
  • Ignition OFF.
  • Disconnect and inspect the IPC and all related in-line connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary
  • Reconnect the IPC and all related in-line connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new IPC .
REFER to: Instrument Panel Cluster (IPC) (413-01 Instrumentation, Message Center and Warning Chimes, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

L9 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) OPERATION
  • Ignition OFF.
  • Disconnect and inspect GSM C2532 and all related in-line electrical connectors.
  • Using a good light source, inspect all disconnected electrical connectors for the following:
    • corrosion - install new connector or terminal and clean the module pins
    • damaged or bent pins - install new terminals or pins
    • pushed-out pins - install new pins as necessary
    • spread terminals - install new terminals as necessary
  • Reconnect GSM C2532 and all related in-line electrical connectors. Make sure they seat and latch correctly.
  • Using the diagnostic scan tool, clear all diagnostic trouble codes (DTCs).
  • Carry out the GSM self-test.

Is DTC U0155 still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB (general service bulletin), SSM (special service message) or FSA (Field Service Action). If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new GSM .
REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST M: DTC U0301

Refer to Wiring Diagrams Cell 14 for schematic and connector information.

Normal Operation and Fault Conditions

The GSM communicates with the PCM through CAN and HS-CAN2 messages.

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
GSM U0301:00 Software Incompatibility with ECM/PCM: No Sub Type Information The GSM detected the incorrect PCM software is installed.

Possible Sources

  • PCM calibration
  • PCM
M1 PROGRAM THE PCM (POWERTRAIN CONTROL MODULE) WITH THE LATEST SOFTWARE
  • Ignition ON.
  • Using a diagnostic scan tool, clear all DTC s from the GSM
  • Reprogram the PCM with the latest calibration.
    REFER to: Module Programming (418-01A Module Configuration, General Procedures).
  • Using a diagnostic scan tool, carry out the PCM and GSM self-tests.

Is DTC U0301 present in the GSM ?
Yes
   Click here to access Guided Routine (PCM).
No The fault is not present at this time. It may have been caused by a module programming error.

PINPOINT TEST N: TRANSMISSION STUCK IN PARK POSITION

Normal Operation and Fault Conditions

  • GSM
    • Resolve any communication diagnostic trouble codes (DTCs) between the GSM and the PCM .
  • PCM
    • Resolve any TR sensor diagnostic trouble codes (DTCs).
  • Park lock pawl solenoid
    • Check the park lock pawl solenoid pin for being stuck. REFER to: Park Lock Pawl Solenoid (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, Removal and Installation).
  • Park lock pawl valve
    • Disassemble the main control valve body and inspect the park lock pawl valve and bore. If the valve or bore is damaged, INSTALL a new main control valve body. REFER to: Main Control Valve Body (307-01 Automatic Transmission) .
  • Park pawl and park pawl actuator rod
    • Inspect the park pawl and park pawl actuator rod for damage or binding. INSTALL new parts as necessary. REFER to: Transmission (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, Overhaul).

Possible Sources

  • GSM or PCM diagnostic trouble codes (DTCs)
  • Park lock pawl solenoid
  • Park lock pawl valve
  • Park pawl actuator rod
  • Park pawl
Diagnostic steps are not provided for this symptom or DTC.  REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).
PINPOINT TEST O: TRANSMISSION RETURNS TO PARK AUTOMATICALLY

Normal Operation and Fault Conditions

  • The criteria for the return to park feature was met
    • Check the system for normal operation. REFER to: External Controls - System Operation and Component Description (307-05 Automatic Transmission External Controls, Description and Operation).
  • Driver door ajar switch, circuits, BCM or GSM
    • Open then close the drivers door and cycle the door locks. If the door ajar icon is illuminated on the IPC with the door closed, or if the power door locks are not working correctly, REFER to: Locks, Latches and Entry Systems (501-14 Handles, Locks, Latches and Entry Systems, Diagnosis and Testing).
    • If the door ajar and locks are working correctly, GO to Pinpoint Test E

Possible Sources

  • Normal operation
  • Connector or terminal damaged, or circuit open or shorted
  • Door lock or latch
  • GSM
Diagnostic steps are not provided for this symptom or DTC.  REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).
PINPOINT TEST P: TRANSMISSION STUCK IN DRIVE

Normal Operation and Fault Conditions

  • GSM
    • Check for GSM diagnostic trouble codes (DTCs).
  • PCM
    • Check for clutch fault or communication diagnostic trouble codes (DTCs) in the PCM .
  • Park lock pawl solenoid pin stuck
    • Check the park lock pawl solenoid pin for being stuck extended. REFER to: Park Lock Pawl Solenoid (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, Removal and Installation).
  • Internal transmission components damaged
    • Check the park lock pawl valve, park pawl actuator and park pawl. REFER to: Transmission (307-01 Automatic Transmission - 10-Speed Automatic Transmission – 10R80, Overhaul).

Possible Sources

  • Internal transmission components
  • GSM
Diagnostic steps are not provided for this symptom or DTC.  REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).
PINPOINT TEST Q: GEAR SELECT BUTTON SLOW TO RETURN

Normal Operation and Fault Conditions

  • Instrument panel center finish panel interference with the GSM buttons on either side of the GSM
    • Remove the center finish panel surrounding the GSM . Inspect the panel for interference around the GSM gear select buttons. Reinstall the panel. REFER to: Instrument Panel Center Finish Panel (501-12 Instrument Panel and Console, Removal and Installation).
  • Debris or interference around the buttons in the GSM .
    • Inspect the GSM for any debris or interference around the gear select buttons. Clean as necessary.
  • GSM
    • If a gear select button is still slow to return after removing any debris or interference, INSTALL a new GSM . REFER to: Gear Shift Module (GSM) (307-05 Automatic Transmission External Controls, Removal and Installation).

Possible Sources

  • Instrument panel center finish panel
  • Debris or interference
  • GSM
Diagnostic steps are not provided for this symptom or DTC.  REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

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