Ford Explorer Quiz
Electrical

Diagnosis and Testing - Trailer Lamps

In this manual: Electrical
General Information — 41Chassis — 173Powertrain — 250Electrical — 303Body and Paint — 331
~37min read

Diagnostic Trouble Code (DTC) Chart

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).


Diagnostic Trouble Code Chart


Module Trouble Code Description Action
BCM B1449:12 Trailer Park/Tail Lamp Output: Short to Battery GO to Pinpoint Test C
BCM B1449:14 Trailer Park/Tail Lamp Output: Circuit Shorted to Ground or Open GO to Pinpoint Test C
For Other BCM Diagnostic Trouble Codes (DTCs) - -
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).
TRM B100E: 2A Video Input "A": Signal Stuck in Range
REFER TO: Parking Aid System (413-13B Parking Aid System - Vehicles With Parking Aid Camera, Diagnosis and Testing).
TRM B10E8:4B Secondary Battery Relay "A": Overheated GO to Pinpoint Test E
TRM B13:00:11 Video Output "A": Short to Ground
REFER TO: Parking Aid System (413-13B Parking Aid System - Vehicles With Parking Aid Camera, Diagnosis and Testing).
TRM B13:00:12 Video Output "A": Short to Battery
REFER TO: Parking Aid System (413-13B Parking Aid System - Vehicles With Parking Aid Camera, Diagnosis and Testing).
TRM B15A9:87 On-Demand Video Switch: No Message
REFER TO: Parking Aid System (413-13B Parking Aid System - Vehicles With Parking Aid Camera, Diagnosis and Testing).
TRM B1D08:11 Trailer Left Turn Signal: Short to Ground GO to Pinpoint Test B
TRM B1D08:12 Trailer Left Turn Signal: Short to Battery GO to Pinpoint Test B
TRM B1D09:11 Trailer Right Turn Indicator: Short to Ground GO to Pinpoint Test B
TRM B1D09:12 Trailer Right Turn Signal: Short to Battery GO to Pinpoint Test B
TRM C0052:12 Steering Wheel Position Sensor "Signal A": Short to Battery
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0052:14 Steering Wheel Position Sensor "Signal A": Short to Ground or Open Circuit
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0053:12 Steering Wheel Position Sensor "Signal B": Short to Battery
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0053:14 Steering Wheel Position Sensor "Signal B": Short to Ground or Open Circuit
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0054:12 Steering Wheel Position Sensor "Signal C": Short to Battery
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0054:14 Steering Wheel Position Sensor "Signal C": Short to Ground or Open Circuit
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0055:12 Steering Wheel Position Sensor "Signal D": Short to Battery
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM C0055:14 Steering Wheel Position Sensor "Signal D": Short to Ground or Open Circuit
REFER TO: Flashing Lights, Siren and Speaker System (100-05 Police Equipment, Diagnosis and Testing).
TRM U0100:00 Lost Communication With ECM/PCM "A": No Sub Type Information GO to Pinpoint Test F
TRM U0140:00 Lost Communication With Body Control Module: No Sub Type Information GO to Pinpoint Test G
TRM U0212:00 Lost Communication with Steering Column Control Module: No Sub Type Information GO to Pinpoint Test H
TRM U0422:00 Incorrect Data Received from Body Control Module: No Sub Type Information GO to Pinpoint Test I
TRM U1000:00 Solid State Driver Protection Active - Driver Disabled: No Subtype Information GO to Pinpoint Test K
TRM U2100:00 Initial Configuration Not Complete: No Sub Type Information GO to Pinpoint Test J
TRM U3000:49 Control Module: Internal Electronic Failure GO to Pinpoint Test K

Symptom Charts

Symptom Chart: Trailer Lamps

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).

Condition Possible Sources Action
Module Does Not Respond to Diagnostic Scan Tool
  • Fuse
  • Wiring, Terminals or Connectors
  • Module
REFER TO: Communication Network (418-00 Communication Network, Diagnosis and Testing).
All Trailer Lamps Inoperative Refer to Pinpoint Test GO to Pinpoint Test A
One or more trailer stop/turn lamps inoperative or always on Refer to Pinpoint Test GO to Pinpoint Test B
Trailer Parking Lamps Inoperative or Stay On Refer to Pinpoint Test GO to Pinpoint Test C
Trailer back-up lamps inoperative or always on Refer to Pinpoint Test GO to Pinpoint Test D
Trailer battery charging inoperative/improper operation Refer to Pinpoint Test GO to Pinpoint Test E

Pinpoint Tests


DIAGNOSTIC TEST A: ALL TRAILER LAMPS INOPERATIVE

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (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 evidence of corrosion or damage. If necessary, repair or install a new trailer tow connector.
A1 CHECK THE TRAILER GROUND CIRCUIT FOR A GROUND CONNECTION
  • Ignition OFF.
  • Disconnect: Trailer.
  • Disconnect: Battery Negative Cable.
  • Action:
    Click to display the connectors

    For the 4-way connector


    Positive lead Measurement/Action Negative lead
    4-way connector, pin 4 Ground

    Click to display the connectors

    For the 7-way connector


    Positive lead Measurement/Action Negative lead
    7-way connector, pin 2 Ground

Is the resistance less than 3 ohms?
Yes The vehicle is operating correctly. SEND the trailer to an authorized RV/trailer repair facility.
No GO to A2
A2 CHECK THE TRAILER GROUND CIRCUIT FOR AN OPEN
  • Disconnect: Trailer Tow Connector C4912.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-2 Ground

Is the resistance less than 3 ohms?
Yes INSTALL a new trailer tow connector. CHECK the system for normal operation.
No REPAIR the circuit.
DIAGNOSTIC TEST B: ONE OR MORE TRAILER STOP/TURN LAMPS INOPERATIVE OR ALWAYS ON

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM B1D08:11 Trailer Left Turn Lamp: Short to Ground Continuous memory and on-demand DTC that sets when the TRM detects a short to ground in the left trailer stop/turn lamp output circuit.
TRM B1D08:12 Trailer Left Turn Indicator: Short to Battery Continuous memory and on-demand DTC that sets when the TRM detects a short to voltage in the left trailer stop/turn lamp output circuit.
TRM B1D09:11 Trailer Right Turn Indicator: Short to Ground Continuous memory and on-demand DTC that sets when the TRM detects a short to ground in the right trailer stop/turn lamp output circuit.
TRM B1D09:12 Trailer Right Turn Indicator: Short to Battery Continuous memory and on-demand DTC that sets when the TRM detects a short to voltage in the right trailer stop/turn lamp output circuit.

Possible Sources

  • Fuse
  • Wiring, Terminals or Connectors
  • Trailer Concern
  • Trailer Tow Connector
  • TRM

Visual Inspection and Pre-checks

  • Check that fuse BCMC 91 (20A) is OK.
  • Inspect the trailer tow connector for evidence of corrosion or damage. If necessary, repair or install a new trailer tow connector.
B1 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR
  • Ignition OFF.
  • Disconnect: Trailer.
  • The ignition is on.
  • For the 4-way connector, while depressing and releasing the brake pedal, measure:
    Click to display connectors

    Left Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    4-way connector, pin 2 Ground

    Click to display the connectors

    Right Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    4-way connector, pin 1 Ground
  • For the 7-way connector, while depressing and releasing the brake pedal, measure:
    Click to display connectors

    Left Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    7-way connector, pin 1 Ground

    Click to display the connectors

    Right Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    7-way connector, pin 4 Ground

Is the voltage greater than 11 volts with the brake pedal depressed and less than 7 volts with the brake pedal released?
Yes The vehicle is operating correctly. SEND the trailer to an authorized RV/trailer repair facility.
No GO to B2
B2 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR (VEHICLE WIRING HARNESS)
  • Ignition OFF.
  • Disconnect: Trailer Tow Connector C4912.
  • The ignition is on.
  • While depressing and releasing the brake pedal, measure:
    Click to display connectors

    Left Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-1 Ground

    Click to display the connectors

    Right Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-4 Ground

Is the voltage greater than 11 volts with the brake pedal depressed and less than 7 volts with the brake pedal released?
Yes INSTALL a new trailer tow connector. CHECK the system for normal operation.
No If both stop/turn lamps are inoperative, GO to B3.
If only one stop lamp is inoperative, GO to B5.
If both stop/turn lamps are always on, GO to B8.
If only one stop lamp is always on, GO to B7.
B3 CHECK THE VOLTAGE AT THE TRM (TRAILER MODULE)
  • Ignition OFF.
  • Disconnect: TRM C2498A.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2498A-2 Ground

Is the voltage greater than 11 volts?
Yes GO to B4
No CHECK that BCMC fuse 91 (20A) is OK. If OK, REPAIR the circuit. If not OK, REFER to Wiring Diagrams to determine the possible causes of the short.
B4 CHECK THE TRM (TRAILER MODULE) GROUND CIRCUIT
  • Ignition OFF.
  • Disconnect: TRM C2498B.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2498A-2 C2498B-1

Is the voltage greater than 11 volts?
Yes GO to B8
No REPAIR the circuit.
B5 CHECK THE TRAILER STOP/TURN LAMP CIRCUITS FOR AN OPEN
  • Ignition OFF.
  • Disconnect: TRM C2498C.
  • The ignition is on.
  • Action:
    Click to display the connectors

    Left Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-1 C2498C-1

    Click to display the connectors

    Right Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-4 C2498C-8

Is the resistance less than 3 ohms?
Yes GO to B6
No REPAIR the circuit.
B6 CHECK THE TRAILER STOP/TURN LAMP CIRCUITS FOR A SHORT TO GROUND
  • Action:
    Click to display the connectors

    Left Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-1 Ground

    Click to display the connectors

    Right Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-4 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to B8
No REPAIR the circuit.
B7 CHECK THE TRAILER STOP/TURN LAMP CIRCUITS FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: TRM C2498C.
  • The ignition is on.
  • Action:
    Click to display the connectors

    Left Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-1 Ground

    Click to display the connectors

    Right Stop/Turn Lamp


    Positive lead Measurement/Action Negative lead
    C4912-4 Ground

Is there voltage present?
Yes REPAIR the circuit.
No GO to B8
B8 CHECK THE TRM (TRAILER MODULE) FOR PROPER 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
    • backed-out pins - install new pins as necessary
  • Connect the TRM connectors. Make sure that they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC PINPOINT TEST C: TRAILER PARK LAMPS INOPERATIVE OR ALWAYS ON

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
BCM B1449:12 Trailer Park/Tail Lamp Output: Short to Battery Continuous memory and on-demand DTC that sets when the BCM detects a short to voltage in the trailer park lamp relay control circuit.
BCM B1449:14 Trailer Park/Tail Lamp Output: Circuit Shorted to Ground or Open Continuous and on-demand DTC that sets when the BCM detects a short to ground in the trailer parking lamp relay control circuit.

Possible Sources

  • Fuse(s)
  • Wiring, Terminals or Connectors
  • Trailer Tow Connector
  • Trailer Concern
  • BCM
  • BCMC

Visual Inspection and Pre-checks

  • Make sure that BCM fuse 55 (20A) is good.
  • Inspect the trailer tow connector for evidence of corrosion or damage. If necessary, repair or install a new trailer tow connector.
C1 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR
  • Ignition OFF.
  • Disconnect: Trailer.
  • The ignition is on.
  • Turn the headlamp switch to the PARKING LAMPS position.
  • For the 4-pin trailer connector, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    4-pin connector, pin 3 Ground
  • For the 7-pin trailer connector, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    7-pin connector, pin 6 Ground
  • Turn the headlamp switch to the OFF position.
  • For the 4-pin trailer connector, measure:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    4-pin connector, pin 3 Ground
  • For the 7-pin trailer 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 with the headlamp switch in the PARK LAMPS position and 0 volts with the headlamp switch in the OFF position?
Yes The vehicle is operating correctly. SEND the trailer to an authorized RV/trailer repair facility.
No If the trailer parking lamps do not illuminate, GO to C2.
If the trailer parking lamps are always on, GO to C7.
C2 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR (VEHICLE WIRING HARNESS)
  • Turn the headlamp switch to the OFF position.
  • Ignition OFF.
  • Disconnect: Trailer Tow Connector C4912.
  • The ignition is on.
  • Turn the headlamp switch to the PARKING LAMPS position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-6 Ground

Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. CHECK the system for normal operation.
No MAKE SURE that BCM fuse 55 (20A) is good. If good, GO to C3. If not good, CONSULT the Wiring Diagrams manual to determine possible causes of the short circuit.
C3 CHECK THE GROUND CIRCUIT CONTROLLED BY THE TRAILER PARKING LAMP RELAY WITH THE PARKING LAMPS ON
  • Turn the headlamp switch to the OFF position.
  • Ignition OFF.
  • Disconnect: BCMC C1035B.
  • The ignition is on.
  • Turn the headlamp switch to the PARKING LAMPS position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    Battery positive C1035B-38

Is the voltage greater than 11 volts?
Yes GO to C6
No GO TO C4
C4 CHECK THE GROUND CONTROLLED CIRCUIT OF THE TRAILER PARKING LAMP RELAY FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Turn the headlamp switch to the OFF position.
  • Disconnect: BCM C2280F.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280F-12 Ground

Is there voltage present?
Yes REPAIR the circuit.
No GO to C5
C5 CHECK THE GROUND CONTROLLED CIRCUIT OF THE TRAILER PARKING LAMP RELAY FOR AN OPEN
  • Ignition OFF.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280F-12 C1035B-38

Is the resistance less than 3 ohms?
Yes GO TO C10
No REPAIR the circuit.
C6 CHECK THE OUTPUT CIRCUIT OF THE TRAILER PARKING LAMP RELAY FOR AN OPEN
  • Ignition OFF.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-6 C1035B-55

Is the resistance less than 3 ohms?
Yes INSTALL a new BCMC.
REFER TO: Body Control Module C (BCMC) (419-10 Multifunction Electronic Modules, Removal and Installation).
No REPAIR the circuit.
C7 CHECK THE GROUND CIRCUIT CONTROLLED BY THE TRAILER PARKING LAMP RELAY WITH THE PARKING LAMPS OFF
  • Turn the headlamp switch to the OFF position.
  • Ignition OFF.
  • Disconnect: BCMC C1035B.
  • The ignition is on.
  • Turn the headlamp switch to the PARKING LAMPS position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    Battery positive C1035B-38

Is there voltage present?
Yes GO TO C8
No GO TO C9
C8 CHECK THE GROUND CONTROLLED CIRCUIT OF THE TRAILER PARKING LAMP RELAY FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280F.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280F-12 Ground

Is the resistance greater than 10000 Ohms?
Yes GO TO C10
No REPAIR the circuit.
C9 CHECK THE OUTPUT CIRCUIT OF THE TRAILER PARKING LAMP RELAY FOR A SHORT TO VOLTAGE
  • Turn the headlamp switch to the OFF position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C1035B-55 Ground

Is there voltage present?
Yes REPAIR the circuit.
No INSTALL a new BCMC.
REFER TO: Body Control Module C (BCMC) (419-10 Multifunction Electronic Modules, Removal and Installation).
C10 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER 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
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST D: TRAILER BACK-UP LAMPS INOPERATIVE OR ALWAYS ON

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

Possible Sources

  • Wiring, Terminals or Connectors
  • Trailer Tow Connector
  • BCM
  • BCMC
  • Trailer Concern

Visual Inspection and Pre-checks

  • Make sure that BCM fuse 58 (10A) is good.
  • Inspect the trailer tow connector for evidence of corrosion or damage. If necessary, repair or install a new trailer tow connector.
D1 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR
  • Ignition OFF.
  • Disconnect: Trailer.
  • Apply the parking brake.
  • The ignition is on.
  • Move the gear selector lever to the REVERSE position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    7-pin connector, pin 7 Ground
  • Move the gear selector lever to the PARK position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    7-pin connector, pin 7 Ground

Is the voltage greater than 11 volts with the gear selector lever in the REVERSE position and 0 volts with the gear selector lever in the PARK position?
Yes The vehicle is operating correctly. SEND the trailer to an authorized RV/trailer repair facility.
No If the trailer back-up lamps do not illuminate, GO to D2.
If the trailer back-up lamps are always on, GO to D7.
D2 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR (VEHICLE WIRING HARNESS)
  • Move the gear selector lever to the PARK position.
  • Ignition OFF.
  • Disconnect: Trailer Tow Connector C4912.
  • Apply the parking brake.
  • The ignition is on.
  • Move the gear selector lever to the REVERSE position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-7 Ground

Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. CHECK the system for normal operation.
No MAKE SURE that BCM fuse 58 (10A) is good. If good, GO to D3. If not good, CONSULT the Wiring Diagrams manual to determine possible causes of the short circuit.
D3 CHECK THE VOLTAGE IN THE TRAILER BACK-UP LAMP RELAY FEED CIRCUIT
  • Move the gear selector lever to the PARK position.
  • Ignition OFF.
  • Disconnect: BCMC C1035B.
  • Apply the parking brake.
  • The ignition is on.
  • Move the gear selector lever to the REVERSE position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C1035B-33 Ground

Is the voltage greater than 11 volts?
Yes GO to D6
No GO to D4
D4 CHECK THE TRAILER BACK-UP LAMP RELAY FEED CIRCUIT FOR A SHORT TO GROUND
  • Move the gear selector lever to the PARK position.
  • Ignition OFF.
  • Disconnect: BCM C2280G.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280G-19 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to D5
No REPAIR the circuit. After the repair:
If no diagnostic trouble codes (DTCs) are present, CHECK the system for normal operation.
If DTC U1000:00 is present, CLEAR the diagnostic trouble codes (DTCs) and REPEAT the self-test (required to enable the lamp output driver if DTC U1000:00 is present).
If DTC U3000:49 is present, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
D5 CHECK THE TRAILER BACK-UP LAMP RELAY FEED CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2280G-19 C1035B-33

Is the resistance less than 3 ohms?
Yes GO to D10
No REPAIR the circuit.
D6 CHECK THE TRAILER BACK-UP LAMP RELAY OUTPUT CIRCUIT FOR AN OPEN
  • Disconnect: BCMC C1035B.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-7 C1035B-49

Is there voltage present?
Yes REPAIR the circuit.
No INSTALL a new BCMC.
REFER TO: Body Control Module C (BCMC) (419-10 Multifunction Electronic Modules, Removal and Installation).
D7 CHECK THE TRAILER BACK-UP LAMP RELAY OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Turn the headlamp switch to the OFF position.
  • Ignition OFF.
  • Disconnect: BCMC C1035B.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-7 Ground

Is there voltage present?
Yes REPAIR the circuit.
No GO to D8
D8 CHECK THE TRAILER BACK-UP LAMP RELAY FEED CIRCUIT FOR VOLTAGE WITH THE PARK POSITION SELECTED
  • Move the gear selector lever to the PARK position.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C1035B-33 Ground

Is there voltage present?
Yes GO to D9
No INSTALL a new BCMC.
REFER TO: Body Control Module C (BCMC) (419-10 Multifunction Electronic Modules, Removal and Installation).
D9 CHECK THE TRAILER BACK-UP LAMP RELAY FEED CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: BCM C2280G.
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C1035B-33 Ground

Is there voltage present?
Yes REPAIR the circuit.
No GO to D10
D10 CHECK THE 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
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST E: TRAILER BATTERY CHARGING INOPERATIVE/IMPROPER OPERATION

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM B10E8:4B Secondary Battery Relay "A": Overtemperature Continuous memory DTC that sets when the TRM detects that the trailer charging output has an internal overtemperature condition.

Possible Sources

  • Fuse
  • Wiring, Terminals or Connectors
  • Trailer Tow Connector
  • TRM
  • Trailer Concern

Visual Inspection and Pre-checks

  • Make sure that BCM fuse 57 (30A) is good.
  • Inspect the trailer tow connector for evidence of corrosion or damage. If necessary, repair or install a new trailer tow connector.
E1 CHECK THE VOLTAGE AT THE TRAILER CONNECTOR
  • Disconnect: Trailer.
  • The ignition is on.
  • Using the diagnostic scan tool, view the TRM parameter identifications (PIDs).

  • Access the TRM and monitor the PWR_PT_RLY (0) PID

  • Command the power point output relay on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C4912-5 Ground

Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. CHECK the system for normal operation.
No GO to E2
E2 CHECK THE CHARGING VOLTAGE AT THE TRM (TRAILER MODULE)
  • Ignition OFF.
  • Disconnect: TRM C2498A.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2498A-1 Ground

Is the voltage greater than 11 volts?
Yes GO to E3
No CHECK that BCM fuse 57 (30A) is good. If good, REPAIR the circuit. If not good, CONSULT the Wiring Diagrams manual to determine possible causes of the short circuit.
E3 CHECK THE TRAILER BATTERY CHARGING CIRCUIT FOR AN OPEN
  • Disconnect: TRM C2498C.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2498C-3 C4912-5

Is the resistance less than 3 ohms?
Yes GO to E4
No REPAIR the circuit.
E4 CHECK THE TRM (TRAILER MODULE) FOR PROPER 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
    • backed-out pins - install new pins as necessary
  • Connect the TRM connectors. Make sure that they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST F : U0100:00

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM U0100:00 Lost Communication With ECM/PCM "A": No Sub Type Information Continuous memory DTC that sets when the TRM does not receive messages from the PCM.

Possible Sources

  • Communication Problem
  • PCM
  • TRM
  • PCM Concern
F1 CONFIRM THE CUSTOMER CONCERN
  • The ignition is on.
  • Make sure the observed symptom is present.

Is the observed symptom present?
Yes GO to F2
No The system is currently operating normally. The DTC may have been set due to high network traffic or an intermittent condition. CLEAR the DTC.
F2 CHECK THE COMMUNICATION NETWORK
  • Using a scan tool, perform the network test.

Do the TRM and PCM pass the network test?
Yes GO to F3
No CHECK that the TRM or PCM is not communicating with the diagnostic scan tool.
REFER TO: Communication Network (418-00 Communication Network, Diagnosis and Testing).
F3 RETRIEVE THE PCM (POWERTRAIN CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scan tool, perform a PCM self-test.

Are any PCM diagnostic trouble codes (DTCs) recorded?
Yes
REFER TO: Engine Control Modules (303-14A Engine Control Modules — 2.3 L EcoBoost (201 kW/273 L PS), Diagnosis and Testing).
REFER TO: Engine Control Modules (303-14B Engine Control Modules — 3 L EcoBoost, Diagnosis and Testing).
REFER TO: Engine Control Modules (303-14C Engine Control Modules — 3.3 L Duratec-V6/3.3 L Duratec-V6 Hybrid (BP), Diagnosis and Testing).
No GO to F4
F4 RECHECK THE TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scanner, clear the TRM Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • The ignition is on.
  • Using the diagnostic scan tool, perform the TRM self-test.

Is DTC U0100:00 still present?
Yes GO to F5
No The system is currently operating correctly. The DTC may have been set due to high network traffic or an intermittent condition.
F5 CHECK THE DTC (DIAGNOSTIC TROUBLE CODE) U0100:00 SET IN OTHER MODULES
  • Using the diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • The ignition is on.
  • Using the diagnostic scan tool, perform a self-test.
  • Retrieve the Diagnostic Trouble Codes (DTCs) from all modules.

Is DTC U0100:00 set in any other module?
Yes GO to F6
No GO to F7
F6 CHECK THE PCM (POWERTRAIN CONTROL MODULE) FOR PROPER OPERATION
  • Disconnect and inspect all PCM and all related line connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the PCM and all related inline connectors. Make sure they are fully seated and locked.
  • 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, STOP this test and FOLLOW the service article instructions. If no service article exists for this concern,
Click here to access the guided routine (PCM). Internet Explorer version 11 or later is required to perform this Pinpoint test.
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
F7 CHECK 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
    • backed-out pins - install new pins as necessary
  • Connect the TRM connectors. Make sure that they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST G : U0140:00

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM U0140:00 Lost Communication With Body Control Module: No Sub Type Information Continuous memory DTC that is set when the TRM does not receive messages from the BCM.

Possible Sources

  • Communication Problem
  • BCM
  • TRM
  • BCM concern
G1 CONFIRM THE CUSTOMER CONCERN
  • The ignition is on.
  • Make sure the observed symptom is present.

Is the observed symptom present?
Yes GO to G2
No The system is currently operating normally. The DTC may have been set due to high network traffic or an intermittent condition. CLEAR the DTC.
G2 CHECK THE COMMUNICATION NETWORK
  • Using a scan tool, perform the network test.

Do the TRM and BCM pass the network test?
Yes GO to G3
No CHECK that the TRM or BCM is not communicating with the diagnostic scan tool.
REFER TO: Communication Network (418-00 Communication Network, Diagnosis and Testing).
G3 RETRIEVE BCM (BODY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using a scan tool, perform the BCM self-test.

Are any BCM Diagnostic Trouble Codes (DTCs) recorded?
Yes
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).
No GO to G4
G4 RECHECK TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scanner, clear the TRM Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • The ignition is on.
  • Using the diagnostic scan tool, perform the TRM self-test.

Is DTC U0140:00 still present?
Yes GO to G5
No The system is currently operating correctly. The DTC may have been set due to high network traffic or an intermittent condition.
G5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0140:00 SET IN OTHER MODULES
  • Using the diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • The ignition is on.
  • Using the diagnostic scan tool, perform a self-test.
  • Retrieve the Diagnostic Trouble Codes (DTCs) from all modules.

Is DTC U0140:00 set in any other module?
Yes GO to G6
No GO to G7
G6 CHECK BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect the BCM and all related inline connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the BCM and all related inline connectors. Make sure they are installed and fully seated.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
G7 CHECK 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
    • backed-out pins - install new pins as necessary
  • Connect the TRM connectors. Make sure that they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST H : U0212:00

For wiring diagrams and connector information, refer to Section 95 Wiring Diagrams.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM U0212:00 Lost Communication with Steering Column Control Module: No Sub Type Information Continuous memory DTC that sets when the TRM does not receive messages from the SCCM.

Possible Sources

  • Communication Problem
  • SCCM
  • TRM
  • SCCM concern
H1 VERIFY CUSTOMER CONCERN
  • The ignition is on.
  • Make sure the observed symptom is present.

Is the observed symptom present?
Yes GO to H2
No The system is currently operating normally. The DTC may have been set due to high network traffic or an intermittent condition. CLEAR the DTC.
H2 CHECK THE COMMUNICATION NETWORK
  • Using a scan tool, perform the network test.

Do the TRM and SCCM pass the network test?
Yes GO to H3
No CHECK that the TRM or BCM is not communicating with the diagnostic scan tool.
REFER TO: Communication Network (418-00 Communication Network, Diagnosis and Testing).
H3 RETRIEVE SCCM (STEERING COLUMN CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scan tool, perform the SCCM self-test.

Are any SCCM diagnostic trouble codes (DTCs) recorded?
Yes
Refer to: Steering Wheel and Column Electrical Components (211-05 Steering Wheel and Column Electrical Components, Diagnosis and Testing).
No GO to H4
H4 RECHECK TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scanner, clear the TRM Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • The ignition is on.
  • Using the diagnostic scan tool, perform the TRM self-test.

Is DTC U0212:00 still present?
Yes GO to H5
No The system is currently operating correctly. The DTC may have been set due to high network traffic or an intermittent condition.
H5 CHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0212:00 SET IN OTHER MODULES
  • Using the diagnostic scan tool, clear all Diagnostic Trouble Codes (DTCs).
  • Ignition OFF.
  • The ignition is on.
  • Using the diagnostic scan tool, perform a self-test.
  • Retrieve the Diagnostic Trouble Codes (DTCs) from all modules.

Is DTC U0140:00 set in any other module?
Yes GO to H6
No GO to H7
H6 CHECK SCCM (STEERING COLUMN CONTROL MODULE) OPERATION
  • Disconnect and inspect the SCCM and all related inline connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the SCCM and all related inline connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new SCCM.
REFER TO: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
H7 CHECK 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
    • backed-out pins - install new pins as necessary
  • Connect the TRM connectors. Make sure that they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST I : U0422:000

For circuit and connector information, refer to Wiring Diagrams Cell 92.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM U0422:00 Incorrect Data Received from Body Control Module: No Sub Type Information Continuous memory and on-demand DTC that sets when the TRM receives invalid network data from the BCM.

Possible Sources

  • BCM
I1 REPEAT ON-DEMAND SELF-TEST AND CHECK DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scan tool, repeat the self-test of the BCM.

Are there any non-network diagnostic trouble codes (DTCs)?
Yes RESOLVE the BCM Diagnostic Trouble Codes (DTCs).
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).
No Diagnose all communication network diagnostic trouble codes (DTC).
REFER to: Communication Network (418-00 Communication Network, Diagnosis and Testing).
DIAGNOSTIC TEST J : U2100:00

For circuit and connector information, refer to Wiring Diagrams Cell 92.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM U2100:00 Initial Configuration Not Complete: No Sub Type Information Continuous memory and on-demand DTC that is set due to an incomplete or incorrect TRM configuration.

Possible Sources

  • TRM
J1 CHECK VEHICLE HISTORY
  • Check the vehicle history for any recent TRM service actions.

Has any recent TRM service been performed?
Yes PERFORM the PMI procedure as directed by the diagnostic scan tool.
REFER TO: Module Programming (418-01 Module Configuration, General Procedures).
No GO to J2
J2 CHECK TRM (TRAILER MODULE) OPERATION
  • Disconnect and inspect the TRM and the associated inline connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - install new terminals/pins
    • backed-out pins - install new pins as necessary
  • Reconnect the TRM and the associated inline connectors. Make sure that it is properly installed and latched.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable service information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
DIAGNOSTIC TEST K : U1000:00, U3000:49

For circuit and connector information, refer to Wiring Diagrams Cell 92.

Normal Operation and Fault Symptoms

REFER TO: Exterior Lighting - Overview (417-01 Exterior Lighting, Description and Operation).
REFER TO: Exterior Lighting - System Operation and Component Description (417-01 Exterior Lighting, Description and Operation).

DTC Fault Trigger Conditions

Trouble Code Description Fault Trigger Condition
TRM U1000:00 Solid State Driver Protection Active - Driver Disabled: No Sub Type Information Continuous memory and on-demand DTC that sets when the module temporarily disables the output due to excessive current draw (for example, a short to ground). The TRM cannot turn on the output until the cause of the short circuit is repaired. FIRST, REFER to all other diagnostic trouble codes (DTCs). After the cause of the problem is repaired, CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test.
TRM U3000:49 Control Module: Internal Electronic Failure Continuous memory and on-demand DTC that sets when the module permanently disables the output because the excessive current draw fault exceeded the limits the TRM can withstand. The cause of the excessive current draw MUST be repaired before a new TRM is installed. FIRST, REFER to all other diagnostic trouble codes (DTCs). After the cause of the problem is repaired, INSTALL a new TRM.

Possible Sources

  • TRM
K1 REPEAT ON-DEMAND SELF-TEST AND CHECK TRM (TRAILER MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Using the diagnostic scanner, 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 information: TSB, GSB, SSM or FSA. If a service article exists for this concern, STOP this test and FOLLOW the service article instructions. If no service article exists, INSTALL a new TRM.
REFER TO: Trailer Module (TRM) (417-01 Exterior Lighting, Removal and Installation).
No The system is currently operating correctly.

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