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Diagnostic Test

  1. 1) TEST FOR INTERMITTENT CONDITION 

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  2).

    No 

    1. The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
  2. 2) ANTILOCK BRAKE MODULE - INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Antilock Brake Module harness connector.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  3).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace the Antilock Brake Module in accordance with the service information.
    2. Perform ABS VERIFICATION TEST .
  3. 3) POWERTRAIN CONTROL MODULE - INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Powertrain Control Module C1 harness connector.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  4).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace and program the Powertrain Control Module in accordance with the service information.
    2. Perform POWERTRAIN VERIFICATION TEST .
  4. 4) SHIFT LEVER ASSEMBLY (IF EQUIPPED) - INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Shift Lever Assembly harness connector.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  5).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace the Shift Lever Assembly in accordance with the service information.
    2. Perform BODY VERIFICATION TEST .
  5. 5) STEERING CONTROL MODULE - INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Steering Control Module C1 harness connector.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  6).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace the Steering Control Module in accordance with the service information.
    2. Perform BODY VERIFICATION TEST .
  6. 6) FINAL DRIVE CONTROL MODULE (IF EQUIPPED)- INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Final Drive Control Module C2 harness connector.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  7).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace the Final Drive Control Module in accordance with the service information.
    2. Perform FDCM VERIFICATION TEST .
  7. 7) ENGINE CONTROL MODULE (DIESEL ONLY) - INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Engine Control Module harness connectors.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  8).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace and program the Engine Control Module in accordance with the service information.
    2. Perform ECM VERIFICATION TEST.
  8. 8) TRANSMISSION CONTROL MODULE (3.7L/DIESEL ONLY) - INTERNAL SHORT 

    Turn the ignition off.

    NOTE: Answer yes if the vehicle is not equipped with this module.

    Disconnect the Transmission Control Module C2 harness connector.

    Turn the ignition on.

    With the scan tool, record and erase FCM DTC's.

    Cycle the ignition from on to off 3 times.

    Turn the ignition on.

    With the scan tool, read active FCM DTC's.

    Does the scan tool display U0001-CAN C BUS CIRCUIT as active? 

    Yes 

    1. Go to  9).

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace and program the Transmission Control Module in accordance with the service information.
    2. Perform appropriate TRANSMISSION VERIFICATION TEST.
  9. 9) (D65) CAN C BUS (+) CIRCUIT SHORTED TO VOLTAGE 
    Fig 1: Checking CAN C Bus (+) Circuit For Short To Voltage
    GC0017172Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Front Control Module C1 harness connector.

    Turn the ignition on.

    Measure the voltage between the (D65) CAN C Bus (+) circuit and ground.

    Is there any voltage present? 

    Yes 

    1. Repair the (D65) CAN C Bus (+) circuit for a short to voltage.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go to  10).
  10. 10) (D64) CAN C BUS (-) CIRCUIT SHORTED TO VOLTAGE 
    Fig 2: Checking CAN C Bus (-) Circuit Short To Voltage
    GC0017173Courtesy of CHRYSLER LLC

    Measure the voltage between the (D64) CAN C Bus (-) circuit and ground.

    Is there any voltage present? 

    Yes 

    1. Repair the (D64) CAN C Bus (-) circuit for a short to voltage.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go to  11).
  11. 11) (D65) CAN C BUS (+) CIRCUIT SHORTED TO GROUND 
    Fig 3: Checking CAN C Bus (+) Circuit For Short To Ground
    GC0017174Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance between ground and the (D65) CAN C Bus (+) circuit.

    Is any resistance present? 

    Yes 

    1. Repair the (D65) CAN C Bus (+) circuit for a short to ground.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go to  12).
  12. 12) (D64) CAN C BUS (-) CIRCUIT SHORTED TO GROUND 
    Fig 4: Checking CAN C Bus (-) Circuit For Short To Ground
    GC0017175Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (D64) CAN C Bus (-) circuit.

    Is any resistance present? 

    Yes 

    1. Repair the (D64) CAN C Bus (-) circuit for a short to ground.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go to  13).
  13. 13) (D65) CAN C BUS (+) CIRCUIT SHORTED TO (D64) CAN C BUS (-) CIRCUIT 
    Fig 5: Checking CAN C Bus (+) Circuit For Short To CAN C Bus (-) Circuit
    GC0017176Courtesy of CHRYSLER LLC

    Measure the resistance between the (D65) CAN C Bus (+) circuit and the (D64) CAN C Bus (-) circuit.

    Is any resistance present? 

    Yes 

    1. Repair the (D65) CAN C Bus (+) circuit for a short to the (D64) CAN C Bus (-) circuit.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Inspect the wiring and connectors for damage or shorted circuits. If OK, replace and program the Front Control Module in accordance with the service information.
    2. Perform BODY VERIFICATION TEST .
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