Lincoln Navigator Manuals

Lincoln Navigator: Exterior Lighting / Trailer Lamps. Diagnosis and Testing

Lincoln Navigator 2018-2025 Workshop Manual / Lighting / Exterior Lighting / Trailer Lamps. Diagnosis and Testing

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
BCM B1449:12 Trailer Tow Park/Tail Lamp Output: Circuit Short To Battery GO to Pinpoint Test C
BCM B1449:14 Trailer Tow Park/Tail Lamp Output: Circuit Short To Ground Or Open GO to Pinpoint Test C
TRM B1D08:11 Left Trailer Direction Indicator: Circuit Short To Ground GO to Pinpoint Test B
TRM B1D08:12 Left Trailer Direction Indicator: Circuit Short To Battery GO to Pinpoint Test B
TRM B1D09:11 Right Trailer Direction Indicator: Circuit Short To Ground GO to Pinpoint Test B
TRM B1D09:12 Right Trailer Direction Indicator: Circuit Short To Battery GO to Pinpoint Test B
TRM P0604:94 Internal Control Module Random Access Memory (RAM) Error: Unexpected Operation GO to Pinpoint Test M
TRM U0100:87 Lost Communication With ECM/PCM 'A': Missing Message GO to Pinpoint Test F
TRM U0121:87 Lost Communication With Anti-Lock Brake System (ABS) Control Module 'A': Missing Message GO to Pinpoint Test G
TRM U0131:87 Lost Communication With Power Steering Control Module 'A': Missing Message GO to Pinpoint Test H
TRM U0140:87 Lost Communication With Body Control Module: Missing Message GO to Pinpoint Test I
TRM U0143:87 Lost Communication With Body Control Module 'C': Missing Message GO to Pinpoint Test J
TRM U0155:87 Lost Communication With Instrument Panel Cluster (IPC) Control Module: Missing Message GO to Pinpoint Test K
TRM U0415:81 Invalid Data Received from Anti-Lock Brake System (ABS) Control Module 'A': Invalid Serial Data Received GO to Pinpoint Test L
TRM U0415:82 Invalid Data Received from Anti-Lock Brake System (ABS) Control Module 'A': Alive/Sequence Counter Incorrect/Not Updated GO to Pinpoint Test L
TRM U0415:83 Invalid Data Received from Anti-Lock Brake System (ABS) Control Module 'A': Value Of Signal Protection Calculation Incorrect GO to Pinpoint Test L
TRM U0423:56 Invalid Data Received from Instrument Panel Cluster Control Module: Invalid/Incompatible Configuration GO to Pinpoint Test L
TRM U1000:00 Solid State Driver Protection Active -Driver Disabled: No Sub Type Information GO to Pinpoint Test N
TRM U202B:61 In-Use Application Signing Key: Signal Calculation Failure GO to Pinpoint Test M
TRM U202B:62 In-Use Application Signing Key: Signal Compare Failure GO to Pinpoint Test M
TRM U2100:00 Initial Configuration Not Complete: No Sub Type Information GO to Pinpoint Test M
TRM U2200:00 Control Module Configuration Memory Corrupt: No Sub Type Information GO to Pinpoint Test M
TRM U3000:49 Control Module: Internal Electronic Failure GO to Pinpoint Test N
TRM U3003:16 Battery Voltage: Circuit Voltage Below Threshold GO to Pinpoint Test O
TRM U3003:17 Battery Voltage: Circuit Voltage Above Threshold GO to Pinpoint Test P
TRM U3008:13 Control Module Ground 'A': Circuit Open GO to Pinpoint Test O

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
Lighting/Glass/Vision > Exterior Lighting > Trailer > Inoperative GO to Pinpoint Test A
Lighting/Glass/Vision > Exterior Lighting > Trailer > Inoperative GO to Pinpoint Test B
Lighting/Glass/Vision > Exterior Lighting > Trailer > Inoperative GO to Pinpoint Test C
Lighting/Glass/Vision > Exterior Lighting > Trailer > Inoperative GO to Pinpoint Test D
Lighting/Glass/Vision > Exterior Lighting > Trailer > Inoperative GO to Pinpoint Test E
Lighting/Glass/Vision > Exterior Lighting > Trailer > Stays On GO to Pinpoint Test B
Lighting/Glass/Vision > Exterior Lighting > Trailer > Stays On GO to Pinpoint Test C
Lighting/Glass/Vision > Exterior Lighting > Trailer > Stays On GO to Pinpoint Test D
Lighting/Glass/Vision > Exterior Lighting > Trailer > Stays On GO to Pinpoint Test E

Symptom 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 Chart


Condition Possible Sources Actions
A module does not respond to the diagnostic scan tool
  • Fuse
  • Wiring, terminals or connectors
  • Module
 
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).
All the trailer lamps are inoperative Refer to the Pinpoint Test   GO to Pinpoint Test A
One or more trailer stop/turn lamps are inoperative or always on Refer to the Pinpoint Test   GO to Pinpoint Test B
The trailer parking lamps are inoperative or always on Refer to the Pinpoint Test   GO to Pinpoint Test C
The trailer reversing lamps are inoperative or always on Refer to the Pinpoint Test   GO to Pinpoint Test D
The trailer battery charging is inoperative/does not operate correctly Refer to the Pinpoint Test   GO to Pinpoint Test E

Pinpoint Tests


PINPOINT TEST A: ALL THE TRAILER LAMPS ARE INOPERATIVE

Refer to Wiring Diagrams Cell 95 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

Possible Sources

  • Wiring, terminals or connectors
  • Trailer tow connector
  • Trailer concern

Visual Inspection and Pre-checks

  • Inspect the trailer tow connector for signs of corrosion or damage. Repair or install a new trailer tow connector as required.
A1 CHECK THE TRAILER TOW GROUND CIRCUIT FOR CONTINUITY TO GROUND
  • Ignition OFF.
  • Disconnect: Trailer.
  • Disconnect: Negative Battery Cable.
  • Measure:
    Click to display connectors

      For 4-Pin Connector


    Positive Lead Measurement / Action Negative Lead
    4-Pin Connector, Pin 4   Ground

    Click to display connectors

      For 7-Pin Connector


    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 2   Ground

Is the resistance less than 3 ohms?
Yes The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
No GO to A2

A2 CHECK THE TRAILER TOW GROUND CIRCUIT FOR AN OPEN
  • Disconnect: Trailer Tow C4099.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-2   Ground

Is the resistance less than 3 ohms?
Yes INSTALL a new trailer tow connector. TEST the system for normal operation.
No REPAIR the circuit.

PINPOINT TEST B: ONE OR MORE TRAILER STOP/TURN LAMPS ARE INOPERATIVE OR ALWAYS ON

Refer to Wiring Diagrams Cell 95 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM B1D08:11 Left Trailer Direction Indicator: Circuit Short To Ground A continuous memory and on-demand DTC that sets when the TRM detects a short to ground from the LH trailer stoplamp/turn signal output circuit.
TRM B1D08:12 Left Trailer Direction Indicator: Circuit Short To Battery A continuous memory and on-demand DTC that sets when the TRM detects a short to voltage from the LH trailer stoplamp/turn signal output circuit.
TRM B1D09:11 Right Trailer Direction Indicator: Circuit Short To Ground A continuous memory and on-demand DTC that sets when the TRM detects a short to ground from the RH trailer stoplamp/turn signal output circuit.
TRM B1D09:12 Right Trailer Direction Indicator: Circuit Short To Battery A continuous memory and on-demand DTC that sets when the TRM detects a short to voltage from the RH trailer stoplamp/turn signal output circuit.

Possible Sources

  • Fuse
  • Wiring, terminals or connectors
  • Trailer concern
  • Trailer tow connector
  • TRM

Visual Inspection and Pre-checks

  • Verify the BCMC (also known as the BJB ) fuse 91 (20A) and fuse 42 (30A) is OK.
  • Inspect the trailer tow connector for signs of corrosion or damage. Repair or install a new trailer tow connector as required.
B1 CHECK FOR VOLTAGE THROUGH THE TRAILER TOW CONNECTOR
  • Ignition OFF.
  • Disconnect: Trailer.
  • Ignition ON.
  • For 4-pin connector, while applying and releasing the brake pedal, measure:
    Click to display connectors

      LH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
    4-Pin Connector, Pin 2   Ground

    Click to display connectors

      RH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
    4-Pin Connector, Pin 1   Ground
  • For 7-pin connector, while applying and releasing the brake pedal, measure:
    Click to display connectors

      LH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 1   Ground

    Click to display connectors

      RH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 4   Ground

Is the voltage greater than 11 volts when the brake pedal is pressed and less than 7 volts when the brake pedal is released?
Yes The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
No GO to B2

B2 CHECK FOR VOLTAGE TO THE TRAILER TOW CONNECTOR (VEHICLE HARNESS)
  • Ignition OFF.
  • Disconnect: Trailer Tow C4099.
  • Ignition ON.
  • While applying and releasing the brake pedal, measure:
    Click to display connectors

      LH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-1   Ground

    Click to display connectors

      RH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-4   Ground

Is the voltage greater than 11 volts when the brake pedal is pressed and less than 7 volts when the brake pedal is released?
Yes INSTALL a new trailer tow connector. TEST the system for normal operation.
No If both stop/turn lamps are inoperative, GO to B3
If only one stop/turn lamp is inoperative, GO to B5
If both stop/turn lamps are always on, GO to B8
If only one stop/turn lamp is always on, GO to B7

B3 CHECK FOR VOLTAGE TO THE TRM (TRAILER MODULE)
  • Ignition OFF.
  • Disconnect: TRM C2498F.
  • Disconnect: TRM C2498C.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498F-14   Ground

    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498C-13   Ground

Is the voltage greater than 11 volts?
Yes GO to B4
No VERIFY the BCMC (also known as the BJB ) fuse 91 (20A) and fuse 42 (30A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.

B4 CHECK THE TRM (TRAILER MODULE) GROUND CIRCUIT
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498F-14   C2498F-12

Is the voltage greater than 11 volts?
Yes GO to B8
No REPAIR the circuit.

B5 CHECK TRAILER STOP/TURN LAMP CIRCUITS FOR AN OPEN
  • Ignition OFF.
  • Disconnect: TRM C2498F.
  • Ignition ON.
  • Measure:
    Click to display connectors

      LH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-1   C2498F-11

    Click to display connectors

      RH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-4   C2498F-13

Is the resistance less than 3 ohms?
Yes GO to B6
No REPAIR the circuit.

B6 CHECK TRAILER STOP/TURN LAMP CIRCUITS FOR A SHORT TO GROUND
  • Measure:
    Click to display connectors

      LH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-1   Ground

    Click to display connectors

      RH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-4   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to B8
No REPAIR the circuit.

B7 CHECK TRAILER STOP/TURN LAMP CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: TRM C2498F.
  • Ignition ON.
  • Measure:
    Click to display connectors

      LH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-1   Ground

    Click to display connectors

      RH Stop/Turn Lamp


    Positive Lead Measurement / Action Negative Lead
      C4099-4   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to B8

B8 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect all TRM 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 TRM 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, 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 C: THE TRAILER PARKING LAMPS ARE INOPERATIVE OR ALWAYS ON

Refer to Wiring Diagrams Cell 95 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
BCM B1449:12 Trailer Tow Park/Tail Lamp Output: Circuit Short To Battery A continuous memory and on-demand DTC that sets when the BCM detects a short to voltage from the trailer parking lamps relay enable circuit.
BCM B1449:14 Trailer Tow Park/Tail Lamp Output: Circuit Short To Ground Or Open A continuous memory and on-demand DTC that sets when the BCM detects an open short to ground from the trailer parking lamps relay enable circuit.

Possible Sources

  • Fuse(s)
  • Wiring, terminals or connectors
  • Trailer tow connector
  • BJB
  • Trailer concern
  • BCM

Visual Inspection and Pre-checks

  • Verify the BCMC (also known as the BJB ) fuse 55 (30A) is OK.
  • Inspect the trailer tow connector for signs of corrosion or damage. Repair or install a new trailer tow connector as required.
C1 CHECK FOR VOLTAGE THROUGH THE TRAILER TOW CONNECTOR
  • Ignition OFF.
  • Disconnect: Trailer.
  • Ignition ON.
  • Place the headlamp switch in the PARKING LAMPS position.
  • For 4-pin connector, measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    4-Pin Connector, Pin 3   Ground
  • For 7-pin connector, measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 6   Ground
  • Place the headlamp switch in the OFF position.
  • For 4-pin connector, measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    4-Pin Connector, Pin 3   Ground
  • For 7-pin connector, measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 6   Ground

Is the voltage greater than 11 volts when the headlamps switch in the PARKING LAMPS position and 0 volts when the headlamps switch in the OFF position?
Yes The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
No If the trailer parking lamps are inoperative, GO to C2
If the trailer parking lamps are always on, GO to C7

C2 CHECK FOR VOLTAGE TO THE TRAILER TOW CONNECTOR (VEHICLE HARNESS)
  • Ignition OFF.
  • Disconnect: Trailer Tow C4099.
  • Ignition ON.
  • Place the headlamp switch in the PARKING LAMPS position.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-6   Ground

Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. TEST the system for normal operation.
No VERIFY the BCMC (also known as the BJB ) fuse 55 (30A) is OK. If OK, GO to C3 If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.

C3 CHECK THE TRAILER TOW PARKING LAMPS RELAY CONTROLLED GROUND CIRCUIT FOR GROUND WITH PARKING LAMPS ON
  • Place the headlamp switch in the OFF position.
  • Ignition OFF.
  • Disconnect: BCMC (also known as the BJB ) C1035C.
  • Ignition ON.
  • Place the headlamp switch in the PARKING LAMPS position.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    Battery Positive   C1035C-36

Is the voltage greater than 11 volts?
Yes GO to C6
No GO to C4

C4 CHECK THE TRAILER TOW PARKING LAMPS RELAY CONTROLLED GROUND CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Place the headlamp switch in the OFF position.
  • Disconnect: BCM C2280F.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280F-12   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to C5

C5 CHECK THE TRAILER TOW PARKING LAMPS RELAY CONTROLLED GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280F-12   C1035C-36

Is the resistance less than 3 ohms?
Yes GO to C10
No REPAIR the circuit.

C6 CHECK THE TRAILER TOW PARKING LAMPS RELAY OUTPUT CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-6   C1035C-56

Is the resistance less than 3 ohms?
Yes GO to C11
No REPAIR the circuit.

C7 CHECK THE TRAILER TOW PARKING LAMPS RELAY CONTROLLED GROUND CIRCUIT FOR GROUND WITH PARKING LAMPS OFF
  • Place the headlamp switch in the OFF position.
  • Ignition OFF.
  • Disconnect: BCMC (also known as the BJB ) C1035C.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    Battery Positive   C1035C-36

Is any voltage present?
Yes GO to C8
No GO to C9

C8 CHECK THE TRAILER TOW PARKING LAMPS RELAY GROUND CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280F.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280F-12   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to C10
No REPAIR the circuit.

C9 CHECK THE TRAILER TOW PARKING LAMPS RELAY OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Place the headlamp switch in the OFF position.
  • Ignition OFF.
  • Disconnect: If equipped, TRM C2498F.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035C-56   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to C11

C10 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM 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 BCM 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 , SSM or FSA . 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.

C11 CHECK FOR CORRECT BCMC (BODY CONTROL MODULE C) OPERATION
  • Disconnect and inspect all BCMC (also knows as the BJB ) 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 BCMC (also knows as the BJB ) 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 , SSM or FSA . 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 BCMC (also knows as the BJB ).
REFER to: Body Control Module C (BCMC) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).
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: THE TRAILER REVERSING LAMPS ARE INOPERATIVE OR ALWAYS ON

Refer to Wiring Diagrams Cell 95 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

Possible Sources

  • Fuse
  • Wiring, terminals or connectors
  • Trailer tow connector
  • BCMC (also known as the BJB )
  • Trailer concern

Visual Inspection and Pre-checks

  • Verify the BCMC (also known as the BJB ) fuse 58 (10A) is OK.
  • Inspect the trailer tow connector for signs of corrosion or damage. Repair or install a new trailer tow connector as required.
D1 CHECK FOR VOLTAGE THROUGH THE TRAILER TOW CONNECTOR
  • Ignition OFF.
  • Disconnect: Trailer.
  • Apply the parking brake.
  • Ignition ON.
  • Place the gear selector lever in REVERSE.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 7   Ground
  • Place the gear selector lever in PARK.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 7   Ground

Is the voltage greater than 11 volts when the gear selector lever is in REVERSE and 0 volts when the gear selector lever is in PARK?
Yes The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
No If the trailer reversing lamps are inoperative, GO to D2
If the trailer reversing lamps are always on, GO to D8

D2 CHECK FOR VOLTAGE TO THE TRAILER TOW CONNECTOR (VEHICLE HARNESS)
  • Place the gear selector lever in PARK.
  • Ignition OFF.
  • Disconnect: Trailer Tow C4099.
  • Apply the parking brake.
  • Ignition ON.
  • Place the gear selector lever in REVERSE.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-7   Ground

Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. TEST the system for normal operation.
No VERIFY the BCMC (also known as the BJB ) fuse 58 (10A) is OK. If OK, GO to D3 If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.

D3 CHECK THE TRAILER TOW REVERSING LAMPS RELAY ENERGIZE CIRCUIT FOR VOLTAGE
  • Place the gear selector lever in PARK.
  • Ignition OFF.
  • Disconnect: BCMC (also known as the BJB ) C1035B.
  • Apply the parking brake.
  • Ignition ON.
  • Place the gear selector lever in the REVERSE.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035B-38   Ground

Is the voltage greater than 11 volts?
Yes GO to D4
No GO to D5

D4 CHECK THE TRAILER TOW REVERSING LAMPS RELAY GROUND CIRCUIT
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035B-38   C1035C-1

Is the voltage greater than 11 volts?
Yes GO to D7
No REPAIR the circuit.

D5 CHECK THE TRAILER TOW REVERSING LAMPS RELAY ENERGIZE CIRCUIT FOR A SHORT TO GROUND
  • Place the gear selector lever in PARK.
  • Ignition OFF.
  • Disconnect: BCM C2280G.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280G-19   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to D6
No REPAIR the circuit.

D6 CHECK THE TRAILER TOW REVERSING LAMPS RELAY ENERGIZE CIRCUIT FOR AN OPEN
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280G-19   C1035B-38

Is the resistance less than 3 ohms?
Yes GO to D11
No REPAIR the circuit.

D7 CHECK THE TRAILER TOW REVERSING LAMPS RELAY OUTPUT CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: BCMC (also known as the BJB ) C1035D.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-7   C1035D-4

Is the resistance less than 3 ohms?
Yes GO to D12
No REPAIR the circuit.

D8 CHECK THE TRAILER TOW REVERSING LAMPS RELAY OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Place the headlamp switch in the OFF position.
  • Ignition OFF.
  • Disconnect: BCMC (also known as the BJB ) C1035D.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-7   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to D9

D9 CHECK THE TRAILER TOW REVERSING LAMPS RELAY ENERGIZE CIRCUIT FOR VOLTAGE IN PARK
  • Place the gear selector lever in PARK.
  • Ignition OFF.
  • Disconnect: BCMC (also known as the BJB ) C1035B.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035B-38   Ground

Is any voltage present?
Yes GO to D10
No GO to D12

D10 CHECK THE TRAILER TOW REVERSING LAMPS RELAY ENERGIZE CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: BCM C2280G.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035B-38   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to D11

D11 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM 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 BCM 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 , SSM or FSA . 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, Diagnosis and Testing).
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.

D12 CHECK FOR CORRECT BCMC (BODY CONTROL MODULE C) OPERATION
  • Disconnect and inspect all BCMC (also knows as the BJB ) 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 BCMC (also knows as the BJB ) 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 , SSM or FSA . 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 BCMC (also knows as the BJB ).
REFER to: Body Control Module C (BCMC) (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.

PINPOINT TEST E: THE TRAILER BATTERY CHARGING IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

Refer to Wiring Diagrams Cell 95 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

Possible Sources

  • Fuse
  • Wiring, terminals or connectors
  • Trailer tow connector
  • TRM
  • Trailer concern

Visual Inspection and Pre-checks

  • Verify the BCMC (also known as the BJB ) fuse 107 (30A) is OK.
  • Inspect the trailer tow connector for signs of corrosion or damage. Repair or install a new trailer tow connector as required.
E1 CHECK FOR VOLTAGE THROUGH THE TRAILER TOW CONNECTOR

NOTE: For vehicles equipped with push-button start, the trailer battery charging output is disabled when the drivers door is ajar.

  • Disconnect: Trailer.
  • Ignition ON.
  • For vehicles equipped with push-button start, make sure the drivers door is not ajar.
  • Using a diagnostic scan tool, view the TRM Parameter Identifications (PIDs).

  • Access the  TRM  and control the  PWR_PT_RLY  PID

  • Command the Power Point Output Relay active command ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    7-Pin Connector, Pin 5   Ground

Is the voltage greater than 11 volts?
Yes The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
No GO to E2

E2 CHECK FOR VOLTAGE TO THE TRAILER TOW CONNECTOR (VEHICLE HARNESS)
  • Ignition OFF.
  • Disconnect: Trailer Tow C4099.
  • Ignition ON.
  • Using a diagnostic scan tool, view the TRM Parameter Identifications (PIDs).

  • Access the  TRM  and control the  PWR_PT_RLY  PID

  • Command the Power Point Output Relay active command ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C4099-5   Ground

Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. TEST the system for normal operation.
No GO to E3

E3 CHECK FOR CHARGING VOLTAGE TO THE TRM (TRAILER MODULE)
  • Ignition OFF.
  • Disconnect: TRM C2498C.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498C-11   Ground

Is the voltage greater than 11 volts?
Yes GO to E4
No VERIFY the BCMC (also known as the BJB ) fuse 107 (30A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short.

E4 CHECK THE TRAILER TOW BATTERY CHARGE CIRCUIT FOR AN OPEN
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498C-12   C4099-5

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

E5 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect all TRM 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 TRM 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, 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: U0100:87

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0100:87 Lost Communication With ECM/PCM 'A': Missing Message A continuous memory DTC that sets in continuous memory in the TRM if data messages received from the PCM are missing for 5 seconds or longer.

Possible Sources

  • Communication concern
  • Battery voltage concern
  • PCM
  • TRM
F1 VERIFY THE SCAN TOOL COMMUNICATES WITH THE PCM (POWERTRAIN CONTROL MODULE)
  • Ignition ON.
  • Connect the scan tool.
  • Using the diagnostic scan tool, verify that a vehicle session can be established.

Can a vehicle session be established?
Yes GO to F2
No
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

F2 CHECK THE HEADLAMP TRM (TRAILER MODULE) CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODES (CMDTCS)
  • Using a diagnostic scan tool, perform the TRM self-test.
  • Clear the Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Repeat the TRM self-test.

Is DTC U0100:87 set again?
Yes GO to F3
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.

F3 PERFORM THE PCM (POWERTRAIN CONTROL MODULE) SELF-TEST
  • Using a diagnostic scan tool, perform the PCM KOEO and KOER self-test.

Are any PCM Diagnostic Trouble Codes (DTCs) recorded?
Yes Diagnose the PCM Diagnostic Trouble Codes (DTCs). REFER to the Master DTC Chart.
No GO to F4

F4 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0100:87
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Wait 10 seconds.
  • Using a diagnostic scan tool, perform the continuous memory self-test.
  • Retrieve the Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules.

Is DTC U0100:87 set in the ABS module?
Yes
   Click here to access Guided Routine (PCM).
No INSTALL a new TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).

PINPOINT TEST G: U0121:87

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0121:87 Lost Communication With Anti-Lock Brake System (ABS) Control Module 'A': Missing Message A continuous memory DTC that sets in continuous memory if the TRM does not receive data messages from the ABS module through the GWM are missing for 5 seconds or longer.

Possible Sources

  • Communication concern
  • Battery voltage concern
  • ABS module
  • TRM
G1 VERIFY THE CUSTOMER CONCERN
  • Ignition ON.
  • Verify there is an observable symptom present.

Is an observable symptom present?
Yes GO to G2
No The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

G2 CHECK THE COMMUNICATION NETWORK
  • Using a diagnostic scan tool, perform the network test.

Does the ABS module pass the network test?
Yes GO to G3
No
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

G3 PERFORM THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE SELF-TEST
  • Using a diagnostic scan tool, perform the ABS module self-test.

Are any Diagnostic Trouble Codes (DTCs) recorded?
Yes
REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).
No GO to G4

G4 RECHECK THE TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

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

  • Using a diagnostic scan tool, clear the Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Repeat the TRM self-test.

Is DTC U0121:87 still present?
Yes GO to G5
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.

G5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0121:87 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Wait 10 seconds.
  • Using a diagnostic scan tool, perform the continuous memory self-test.
  • Retrieve the Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules.

Is DTC U0121:87 set in the BCM ?
Yes INSTALL a new EBB unit ( HCU and ABS module assembly).
No INSTALL a new TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).

PINPOINT TEST H: U0131:87

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0131:87 Lost Communication With Power Steering Control Module 'A': Missing Message A continuous memory DTC that sets in continuous memory if the TRM does not receive data messages from the PSCM module are missing for 5 seconds or longer.

Possible Sources

  • Communication concern
  • Battery voltage concern
  • PSCM
  • TRM
H1 VERIFY THE CUSTOMER CONCERN
  • Ignition ON.
  • Verify there is an observable symptom present.

Is an observable symptom present?
Yes GO to H2
No The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

H2 CHECK THE COMMUNICATION NETWORK
  • Using a diagnostic scan tool, perform the network test.

Does the PSCM pass the network test?
Yes GO to H3
No
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

H3 PERFORM THE PSCM (POWER STEERING CONTROL MODULE) SELF-TEST
  • Using a diagnostic scan tool, perform the PSCM self-test.

Are any Diagnostic Trouble Codes (DTCs) recorded?
Yes
REFER to: Power Steering (211-02 Power Steering, Diagnosis and Testing).
No GO to H4

H4 RECHECK THE TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

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

  • Using a diagnostic scan tool, clear the Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Repeat the TRM self-test.

Is DTC U0131:87 still present?
Yes GO to H5
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.

H5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0131:87 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Wait 10 seconds.
  • Using a diagnostic scan tool, perform the continuous memory self-test.
  • Retrieve the Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules.

Is DTC U0131:87 set in the BCM ?
Yes INSTALL a new PSCM (part of the steering gear).
REFER to: Steering Gear (211-02 Power Steering, Removal and Installation).
No INSTALL a new TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).

PINPOINT TEST I: U0140:87

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0140:87 Lost Communication With Body Control Module: Missing Message A continuous memory DTC that sets when the TRM if messages received from the BCM are missing.

Possible Sources

  • Communication concern
  • BCM
  • TRM
I1 VERIFY THE CUSTOMER CONCERN
  • Ignition ON.
  • Verify that there is an observable symptom present.

Is an observable symptom present?
Yes GO to I2
No The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. CLEAR the DTC .

I2 CHECK THE COMMUNICATION NETWORK
  • Using a diagnostic scan tool, perform a network test.

Does the TRM pass the network test?
Yes GO to I3
No
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

I3 RETRIEVE THE BCM (BODY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, perform the BCM self-test.

Are any BCM Diagnostic Trouble Codes (DTCs) recorded?
Yes REPAIR the BCM Diagnostic Trouble Codes (DTCs). REFER to the Master DTC Chart.
No GO to I4

I4 RECHECK THE TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, clear the TRM Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the TRM self-test.

Is DTC U0140:87 still present?
Yes GO to I5
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.

I5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0140:87 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the self-test.
  • Retrieve the Diagnostic Trouble Codes (DTCs) from all modules.

Is DTC U0140:87 set in any other module?
Yes GO to I6
No GO to I7

I6 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect all BCM 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 BCM 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 , SSM or FSA . 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.

I7 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect all TRM 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 TRM 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, 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 J: U0143:87

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0143:87 Lost Communication With Body Control Module 'C': Missing Message A continuous memory DTC that sets when the TRM if messages received from the BCMC are missing.

Possible Sources

  • Communication concern
  • BCMC
  • TRM
J1 VERIFY THE CUSTOMER CONCERN
  • Ignition ON.
  • Verify that there is an observable symptom present.

Is an observable symptom present?
Yes GO to J2
No The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. CLEAR the DTC .

J2 CHECK THE COMMUNICATION NETWORK
  • Using a diagnostic scan tool, perform a network test.

Does the TRM pass the network test?
Yes GO to J3
No
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

J3 RETRIEVE THE BCMC (BODY CONTROL MODULE C) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, perform the BCMC self-test.

Are any BCMC Diagnostic Trouble Codes (DTCs) recorded?
Yes REPAIR the BCMC Diagnostic Trouble Codes (DTCs). REFER to the Master DTC Chart.
No GO to J4

J4 RECHECK THE TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, clear the TRM Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the TRM self-test.

Is DTC U0143:87 still present?
Yes GO to J5
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.

J5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0143:87 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the self-test.
  • Retrieve the Diagnostic Trouble Codes (DTCs) from all modules.

Is DTC U0143:87 set in any other module?
Yes GO to J6
No GO to J7

J6 CHECK FOR CORRECT BCMC (BODY CONTROL MODULE C) OPERATION
  • Disconnect and inspect all BCMC 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 BCMC 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 , SSM or FSA . 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 BCMC .
REFER to: Body Control Module C (BCMC) (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.

J7 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect all TRM 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 TRM 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, 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 K: U0155:87

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0155:87 Lost Communication With Instrument Panel Cluster (IPC) Control Module: Missing Message A continuous memory DTC that sets when the TRM if messages received from the IPC are missing.

Possible Sources

  • Communication concern
  • IPC
  • TRM
K1 VERIFY THE CUSTOMER CONCERN
  • Ignition ON.
  • Verify that there is an observable symptom present.

Is an observable symptom present?
Yes GO to K2
No The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. CLEAR the DTC .

K2 CHECK THE COMMUNICATION NETWORK
  • Using a diagnostic scan tool, perform a network test.

Does the TRM pass the network test?
Yes GO to K3
No
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

K3 RETRIEVE THE IPC (INSTRUMENT PANEL CLUSTER) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, perform the BCMC self-test.

Are any IPC Diagnostic Trouble Codes (DTCs) recorded?
Yes REPAIR the IPC Diagnostic Trouble Codes (DTCs). REFER to the Master DTC Chart.
No GO to K4

K4 RECHECK THE TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, clear the TRM Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the TRM self-test.

Is DTC U0155:87 still present?
Yes GO to K5
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.

K5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0155:87 SET IN OTHER MODULES
  • Using a diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the self-test.
  • Retrieve the Diagnostic Trouble Codes (DTCs) from all modules.

Is DTC U0155:87 set in any other module?
Yes GO to K6
No GO to K7

K6 CHECK FOR CORRECT IPC (INSTRUMENT PANEL CLUSTER) OPERATION
  • Disconnect and inspect all IPC 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 BCMC 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 , SSM or FSA . 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.

K7 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect all TRM 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 TRM 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, 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 L: U0415:81, U0415:82, U0415:83 ,U0423:56

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

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U0415:81 Invalid Data Received from Anti-Lock Brake System (ABS) Control Module 'A': Invalid Serial Data Received A continuous memory DTC that sets when the TRM receives invalid network data from the ABS module.
TRM Continuous U0415:82 Invalid Data Received from Anti-Lock Brake System (ABS) Control Module 'A': Alive/Sequence Counter Incorrect/Not Updated A continuous memory DTC that sets when the TRM receives invalid network data from the ABS module.
TRM Continuous U0415:83 Invalid Data Received from Anti-Lock Brake System (ABS) Control Module 'A': Value Of Signal Protection Calculation Incorrect A continuous memory DTC that sets when the TRM receives invalid network data from the ABS module.
TRM Continuous U0423:56 Invalid Data Received from Instrument Panel Cluster Control Module: Invalid/Incompatible Configuration A continuous memory DTC that sets when the TRM receives invalid network data from the IPC .

Possible Sources

  • TRM
L1 REPEAT THE ON-DEMAND SELF-TEST AND CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS)
  • For DTC U0415:81, U0415:82, or U0415:83 Using a diagnostic scan tool, repeat the ABS module self-test.
  • For DTC U0423:56, Using a diagnostic scan tool, repeat the IPC self-test.

Are any non-network Diagnostic Trouble Codes (DTCs) present?
Yes For DTC U0415:81, U0415:82, or U0415:83, REPAIR the ABS Diagnostic Trouble Codes (DTCs).
REFER to: Anti-Lock Brake System (ABS) and Stability Control (206-09 Anti-Lock Brake System (ABS) and Stability Control, Diagnosis and Testing). For DTC U0423:56, REPAIR the IPC Diagnostic Trouble Codes (DTCs).
REFER to: Instrumentation, Message Center and Warning Chimes (413-01 Instrumentation, Message Center and Warning Chimes, Diagnosis and Testing).
or 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 Diagnose all network Diagnostic Trouble Codes (DTCs).
REFER to: Controller Area Network (CAN) Module Communications Network (418-00A Controller Area Network (CAN) Module Communications Network, Diagnosis and Testing).

PINPOINT TEST M: P0604:94, U2100:00, U2200:00

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous P0604:94 Internal Control Module Random Access Memory (RAM) Error: Unexpected Operation A continuousDTC that sets due to a TRM RAM error.
TRM Continuous U202B:61 In-Use Application Signing Key: Signal Calculation Failure A continuousDTC that sets due the TRM possibly being in development mode.
TRM Continuous U202B:62 In-Use Application Signing Key: Signal Compare Failure A continuousDTC that sets due the TRM possibly being in development mode.
TRM Continuous U2100:00 Initial Configuration Not Complete: No Sub Type Information A continuousDTC that sets due to incomplete or incorrect TRM configuration.
TRM Continuous U2200:00 Control Module Configuration Memory Corrupt: No Sub Type Information A continuous memory and on-demand DTC that sets due to incomplete or incorrect TRM configuration.

Possible Sources

  • TRM
M1 CHECK VEHICLE HISTORY
  • Check vehicle history for recent service actions with the TRM .

Where there any recent TRM service actions?
Yes PERFORM the PMI procedure as directed by the scan tool.
REFER to: Module Programming (418-01A Module Configuration, General Procedures).
No GO to M2

M2 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect the TRM 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 TRM and related in-line connectors. Make sure it seats and latches 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, 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 N: U1000:00, U3000:49

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U1000:00 Solid State Driver Protection Active -Driver Disabled: No Sub Type Information A continuous memory DTC that sets when the module has temporarily disabled an output because an excessive current draw exists (such as a short to ground). The TRM cannot enable the output until the cause of the short is corrected. ADDRESS all other Diagnostic Trouble Codes (DTCs) first. After the cause of the concern is corrected, CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test.
TRM Continuous U3000:49 Control Module: Internal Electronic Failure A continuous memory DTC that sets when the module has permanently disabled an output because an excessive current draw fault (such as a short to ground) has exceeded the limits that the TRM can withstand. The cause of the excessive current draw MUST be corrected before a new TRM is installed. ADDRESS all other Diagnostic Trouble Codes (DTCs) first. After the cause of the concern is corrected, INSTALL a new TRM .

Possible Sources

  • TRM
N1 REPEAT THE ON-DEMAND SELF-TEST AND CHECK FOR TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, clear the Diagnostic Trouble Codes (DTCs) and repeat the TRM self-test.

Does TRM DTC U1000:00 or U3000:49 return?
Yes CHECK OASIS for any applicable service articles: TSB , GSB , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is operating correctly at this time.

PINPOINT TEST O: U3003:16

Refer to Wiring Diagrams Cell 95 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U3003:16 Battery Voltage: Circuit Voltage Below Threshold A continuous memory DTC that sets in the TRM if the TRM detects low battery voltage on the voltage supply input.
TRM Continuous U3008:13 Control Module Ground 'A': Circuit Open A continuous memory DTC that sets in the TRM if the TRM detects low battery voltage on the voltage supply input.

Possible Sources

  • Wiring, terminals or connectors
  • Battery concern
  • Charging system concern
  • TRM
O1 CARRY OUT THE TRM (TRAILER MODULE) SELF-TEST
  • Ignition ON.
  • Using a diagnostic scan tool, clear the Diagnostic Trouble Codes (DTCs).
  • Wait 10 seconds.
  • Using a diagnostic scan tool, perform the TRM self-test.

Is DTC U3003:16 still present?
Yes GO to O2
No The system is operating correctly at this time. The DTC may have been set due to a previous low battery voltage condition.

O2 CHECK FOR CHARGING SYSTEM DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a diagnostic scan tool, retrieve all Continuous Memory Diagnostic Trouble Codes (CMDTCs).

Are any charging system Diagnostic Trouble Codes (DTCs) recorded?
Yes Diagnose the PCM DTC . REFER to the Master DTC Chart.
No GO to O3

O3 CHECK THE BATTERY CONDITION AND STATE OF CHARGE
  • Check the battery condition and verify the battery is fully charged.
    REFER to: Battery (414-01 Battery, Mounting and Cables, Diagnosis and Testing).

Is the battery OK and fully charged?
Yes GO to O4
No CHARGE or INSTALL a new battery.
For charging a battery,
REFER to: Battery Charging (414-01 Battery, Mounting and Cables, General Procedures). For installing a new battery.
REFER to: Battery (414-01 Battery, Mounting and Cables, Removal and Installation).

O4 CHECK THE TRM (TRAILER MODULE) VOLTAGE SUPPLY
  • Ignition OFF.
  • Disconnect: TRM C2498F.
  • Ignition ON.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498F-14   Ground

Are the voltages greater than 11 volts?
Yes GO to O5
No REPAIR the circuit in question for high resistance.

O5 CHECK THE TRM (TRAILER MODULE) PROCESSOR GROUND
  • Ignition OFF.
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2498F-12   Ground

Is the resistance less than 3 ohms?
Yes GO to O6
No REPAIR the circuit for high resistance.

O6 CHECK FOR CORRECT TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect the TRM connector.
  • 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 TRM connector. Make sure it seats and latches 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 , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is operating correctly at this time. The concern may have been caused by the module connection. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST P: U3003:17

Refer to Wiring Diagrams Cell 92 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
TRM Continuous U3003:17 Battery Voltage: Circuit Voltage Above Threshold A continuous memory DTC that sets in the HCM if the TRM detects high battery voltage on the voltage supply input.

Possible Sources

  • Charging system concern
  • TRM
P1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS) P0563 (PCM (POWERTRAIN CONTROL MODULE) ), U3003:17 OR U3006:17 SET IN OTHER MODULES
  • Ignition ON.
  • Using a diagnostic scan tool, retrieve the Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules.

Is DTC U3003:17, U3006:17 or P0563 ( PCM ) set in more than one module?
Yes Diagnose the DTC . REFER to the Master DTC Chart.
No GO to P2

P2 CHECK THE BATTERY VOLTAGE
  • Turn off all interior/exterior lights and accessories.
  • Start and run the engine at approximately 2,000 RPM for 3 minutes while monitoring the battery voltage.

Does the battery voltage rise to 15.9 volts or higher?
Yes Diagnose the charging system.
REFER to: Charging System - 3.5L EcoBoost (272kW/370PS) (414-00 Charging System - General Information, Diagnosis and Testing).
No GO to P3

P3 RECHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U3003:17
  • Turn the engine off.
  • Ignition ON.
  • Using a diagnostic scan tool, perform the self-test.
  • Clear the Continuous Memory Diagnostic Trouble Codes (CMDTCs).
  • Carry out the TRM self-test.

Is DTC U3003:17 still present?
Yes CHECK OASIS for any applicable service articles: TSB , GSB , SSM or FSA . 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 TRM .
REFER to: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
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.


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    REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

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