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DTC U0146

DTC U0146  : F-CAN Malfunction (PCM-CAN Gateway)

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
U0146 F-CAN Malfunction (PCM-CAN Gateway)    

DTC (PGM-FI)

  1. CAN gateway system DTC check

    -1. Turn the vehicle to the ON mode.

    -2. Check for CAN gateway system DTCs with the HDS.

    DTC Description DTC
       

    DTC (CAN GATEWAY)

    Are any DTCs indicated?

    YES 

    Go to the troubleshooting for CAN gateway system DTC(s) .

    NO 

    Go to step 2.

  2. F-CAN circuit communication check

    -1. Select the Function Test in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

    F-CAN Bus Connected Unit Check

    Which result is indicated?

    PCM (Bus A) is Not Available

    Go to step 3.

    PCM (Bus C) is Not Available

    Go to step 4.

    PCM is Detected

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

  3. Open wire check (F-CAN A_H line, F-CAN A_L line)

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

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connectors.

    CAN gateway 16P connector
    PCM connector A (50P)

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 16P connector: disconnected
      PCM connector A (50P): disconnected
    Test point 1 CAN gateway 16P connector (female terminals) No. 3:
    Test point 2 PCM connector A (50P) No. 39
    Test point 1 CAN gateway 16P connector (female terminals) No. 11:
    Test point 2 PCM connector A (50P) No. 38
    GHH385668Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN A_H wire and the F-CAN A_L wire are OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC U0146 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the F-CAN A_H wire and/or the F-CAN A_L wire between the PCM (A39, A38) and the CAN gateway.

  4. Open wire check (F-CAN C_H line, F-CAN C_L line)

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

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connectors.

    CAN gateway 16P connector
    PCM connector A (50P)

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 16P connector: disconnected
      PCM connector A (50P): disconnected
    Test point 1 CAN gateway 16P connector (female terminals) No. 5:
    Test point 2 PCM connector A (50P) No. 37
    Test point 1 CAN gateway 16P connector (female terminals) No. 13:
    Test point 2 PCM connector A (50P) No. 36
    GHH385671Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN C_H wire and the F-CAN C_L wire are OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC U0146 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the F-CAN C_H wire and/or the F-CAN C_L wire between the PCM (A37, A36) and the CAN gateway.