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DTC U0155: F-CAN Malfunction (PCM-Gauge Control Module)

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: HOW TO TROUBLESHOOT THE FUEL AND EMISSIONS SYSTEMS or How to Troubleshoot the CVT System(CVT) .

DTC Description Confirmed DTC Pending DTC Freeze Frame
U0155 F-CAN Malfunction (PCM-Gauge Control Module)      

DTC (PGM-FI)

  1. Problem verification:

    - 1. Turn the vehicle to the ON mode.

    - 2. Clear the DTC with the HDS.

    - 3. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC Freeze Frame
    U0155 F-CAN Malfunction (PCM-Gauge Control Module)      

    Is DTC U0155 indicated?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the gauge control module and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

  2. Gauge control module DTC check:

    - 1. Check for gauge control module DTCs with the HDS.

    DTC Description DTC
    U0029 F-CAN communication line error  
    U0100 Gauge control module lost communication with ENG/AT  

    Is DTC U0029 and/or U0100 indicated?

    YES 

    Go to step 3.

    NO 

    Do the gauge control module input test .

  3. Open wire check (F-CAN_H line):

    - 1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Jump the SCS line with the HDS.

    SCS Short

    - 3. Disconnect the following connectors.

    PCM connector A (51P)
    Gauge control module 32P connector

    - 4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (51P): disconnected
      Gauge control module 32P connector: disconnected
    Test point 1 Gauge control module 32P connector No. 21
    Test point 2 PCM connector A (51P) No. 2

    Is there continuity?

    YES 

    The F-CAN_H wire is OK. Go to step 4.

    NO 

    Repair an open in the F-CAN_H wire between the PCM (A2) and the gauge control module.

  4. Open wire check (F-CAN_L line):

    - 1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (51P): disconnected
      Gauge control module 32P connector: disconnected
    Test point 1 Gauge control module 32P connector No. 22
    Test point 2 PCM connector A (51P) No. 1

    Is there continuity?

    YES 

    The F-CAN_L wire is OK. Substitute a known-good gauge control module , then recheck. If DTC U0155 is not indicated after substitution, replace the original gauge control module .

    NO 

    Repair an open in the F-CAN_L wire between the PCM (A1) and the gauge control module.