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DTC U0122 (Keyless Access Power Control Unit) (2014 2015 2016 2017)

DTC U0122  : Power Control Unit Lost Communication With VSA Modulator-Control Unit (VSA Message)

DTC Description DTC
U0122 Power Control Unit Lost Communication With VSA Modulator-Control Unit (VSA Message)  

DTC (Power Control Unit)

NOTE:  Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information .

  1. CAN gateway system DTC check

    -1. Check for CAN gateway system DTCs with the HDS.

    DTC Description DTC
    U0029-00 CAN Gateway F-CAN ch A Bus Off  
    U0047-00 CAN Gateway F-CAN ch B Bus Off  
    U0056-00 CAN Gateway F-CAN ch C Bus Off  
    U3000-49 CAN Gateway Internal Failure  

    Is DTC U0029-00, U0047-00, U0056-00, and/or U3000-49 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?

    KEYLESS ACCESS CONTROL UNIT (Bus B) is Not Available

    Go to step 3.

    VSA MODULATOR-CONTROL UNIT (Bus B) is Not Available

    Go to step 5.

    VSA MODULATOR-CONTROL UNIT (Bus C) is Not Available

    Go to step 7.

    KEYLESS ACCESS CONTROL UNIT and VSA MODULATOR-CONTROL UNIT are Detected

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the keyless access control unit, the CAN gateway, and the VSA modulator-control unit.

  3. Open wire check (F-CAN B_H line)

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

    -2. Disconnect the following connectors.

    CAN gateway 24P connector
    Keyless access control unit connector C (24P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Keyless access control unit connector C (24P): disconnected
    Test circuit F-CAN B_H
    Test point 1 CAN gateway 24P connector No. 11 (LT BLU)
    Test point 2 Keyless access control unit connector C (24P) No. 4 (LT BLU)
    GHH348834Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN B_H wire is OK. Go to step 4.

    NO 

    Repair an open in the F-CAN B_H wire between the keyless access control unit and the CAN gateway.

  4. Open wire check (F-CAN B_L line)

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      Keyless access control unit connector C (24P): disconnected
    Test circuit F-CAN A_L
    Test point 1 CAN gateway 24P connector No. 10 (GRY)
    Test point 2 Keyless access control unit connector C (24P) No. 5 (GRY)
    GHH348835Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN B_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the keyless access control unit. Substitute a good-known keyless access control unit , then recheck. If DTC U0122 is not indicated the keyless access control unit was substituted, replace the original keyless access control unit .

    NO 

    Repair an open in the F-CAN B_L wire between the keyless access control unit and the CAN gateway.

  5. Open wire check (F-CAN B_H line)

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

    -2. Disconnect the following connectors.

    CAN gateway 24P connector
    VSA modulator-control unit connector (38P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      VSA modulator-control unit connector (38P): disconnected
    Test circuit F-CAN B_H
    Test point 1 CAN gateway 24P connector No. 11 (LT BLU)
    Test point 2 VSA modulator-control unit connector (38P) No. 38 (LT BLU)
    GHH348836Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN B_H wire is OK. Go to step 6.

    NO 

    Repair an open in the F-CAN B_H wire between the VSA modulator-control unit and the CAN gateway.

  6. Open wire check (F-CAN B_L line)

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      VSA modulator-control unit connector (38P): disconnected
    Test circuit F-CAN B_L
    Test point 1 CAN gateway 24P connector No. 10 (GRY)
    Test point 2 VSA modulator-control unit connector (38P) No. 26 (GRY)
    GHH348837Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN B_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the VSA modulator-control unit. Update the VSA modulator-control unit if it does not have the latest software, then recheck. If DTC U0122 goes away and the VSA modulator-control unit was updated, troubleshooting is complete. If DTC U0122 is still indicated, replace the VSA modulator-control unit .

    NO 

    Repair an open in the F-CAN B_L wire between the VSA modulator-control unit and the CAN gateway.

  7. Open wire check (F-CAN C_H line)

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

    -2. Disconnect the following connectors.

    CAN gateway 24P connector
    VSA modulator-control unit connector (38P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      VSA modulator-control unit connector (38P): disconnected
    Test circuit F-CAN C_H
    Test point 1 CAN gateway 24P connector No. 9 (PUR)
    Test point 2 VSA modulator-control unit connector (38P) No. 31 (PUR)
    GHH348838Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN C_H wire is OK. Go to step 8.

    NO 

    Repair an open in the F-CAN C_H wire between the VSA modulator-control unit and the CAN gateway.

  8. Open wire check (F-CAN C_L line)

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

    Test condition Vehicle OFF (LOCK) mode
      CAN gateway 24P connector: disconnected
      VSA modulator-control unit connector (38P): disconnected
    Test circuit F-CAN C_L
    Test point 1 CAN gateway 24P connector No. 8 (PNK)
    Test point 2 VSA modulator-control unit connector (38P) No. 20 (PNK)
    GHH348839Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F-CAN C_L wire is OK. Check for poor connections or loose terminals at the CAN gateway and the VSA modulator-control unit. Update the VSA modulator-control unit if it does not have the latest software, then recheck. If DTC U0122 goes away and the VSA modulator-control unit was updated, troubleshooting is complete. If DTC U0122 is still indicated, replace the VSA modulator-control unit .

    NO 

    Repair an open in the F-CAN C_L wire between the VSA modulator-control unit and the CAN gateway.

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