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DTC U128D (Windshield Wiper Control Unit) (2014 2015)

DTC U128D  : Lost Communication With Gauge Control Module On B-CAN (VSP or NE Frame)

DTC Description DTC
U128D Lost Communication With Gauge Control Module On B-CAN (VSP or NE Frame)  

DTC (Windshield Wiper Control Unit)

NOTE:  If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -3. Wait for at least 6 seconds.

    -4. Check for DTCs with the HDS.

    DTC Description DTC
    U128D Lost Communication With Gauge Control Module On B-CAN (VSP or NE Frame)  

    Is DTC U128D indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for loose or poor connections.

  2. Determine possible failure area (gauge control module power and ground, B CAN line)

    -1. Select B-CAN CONTROL UNITS INFORMATION from the BODY ELECTRICAL SYSTEM SELECT menu, and then select CHECK CONNECTED CONTROL UNITS.

    -2. Check the DETECT/NOT AVAILABLE information of the GAUGE CONTROL MODULE.

    Is DETECT indicated?

    YES 

    Go to step 8.

    NO 

    Go to step 3.

  3. Fuse check

    -1. Check the following fuses.

    Fuse No. C16 (10 A)
    Location Under-hood fuse/relay box
    Fuse No. D11 (10 A)
    Location Driver's under-dash fuse/relay box

    Is each fuse OK?

    YES 

    Go to step 4.

    NO 

    Replace the fuse. If the fuse blows again, repair a short to ground in the No. C16 (10 A) and/or No. D11 (10 A) fuse circuit (s).

  4. Open wire check (+B BACK UP line)

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

    -2. Disconnect the following connector.

    Gauge control module connector A (32P)

    -3. Measure the voltage between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    Gauge control module connector A (32P): disconnected
    Gauge control module connector A (32P): disconnected
    Test circuit +B BACK UP
    Test point 1 Gauge control module connector A (32P) No. 1 (PNK)
    Test point 2 Body ground
    GHH352760Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The +B BACK UP wire is OK. Go to step 5.

    NO 

    Repair an open or high resistance in the wire.

  5. Open wire check (IG1 METER line)

    -1. Turn the vehicle to the ON mode.

    -2. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
    Gauge control module connector A (32P): disconnected
    Test circuit IG1 METER
    Test point 1 Gauge control module connector A (32P) No. 2 (ORN)
    Test point 2 Body ground
    GHH352761Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The IG1 METER wire is OK. Go to step 6.

    NO 

    Repair an open or high resistance in the wire.

  6. Open wire check (GND lines)

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

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

    Test condition Vehicle OFF (LOCK) mode
    Gauge control module connector A (32P): disconnected
    Test circuit GND
    Test point 1 Gauge control module connector A (32P) No. 16 (BLK)
    Test point 2 Body ground
    Test circuit GND
    Test point 1 Gauge control module connector A (32P) No. 32 (BLK)
    Test point 2 Body ground
    GHH352762Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The GND wires are OK. Go to step 7.

    NO 

    Repair an open or high resistance in the ground wire or poor ground (G501).

  7. Open wire check (B CAN lines)

    -1. Disconnect the following connector.

    Windshield wiper control unit 6P connector

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

    Test condition Vehicle OFF (LOCK) mode
    Gauge control module connector A (32P): disconnected
    Windshield wiper control unit 6P connector: disconnected
    Test circuit B CAN-H
    Test point 1 Windshield wiper control unit 6P connector No. 3 (RED)
    Test point 2 Gauge control module connector A (32P) No. 25 (RED)
    GHH352763Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    An open or poor connection in the B CAN-L wire between the windshield wiper control unit and the gauge control module.

    NO 

    An open or poor connection in the B CAN-H wire between the windshield wiper control unit and the gauge control module.

  8. Open wire check (B CAN lines)

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

    -2. Disconnect the following connectors.

    Windshield wiper control unit 6P connector
    Gauge control module connector A (32P)

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

    Test condition Vehicle OFF (LOCK) mode
    Windshield wiper control unit 6P connector: disconnected
    Gauge control module connector A (32P): disconnected
    Test circuit B CAN-H
    Test point 1 Windshield wiper control unit 6P connector No. 3 (RED)
    Test point 2 Gauge control module connector A (32P) No. 25 (RED)
    GHH352764Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    An open or poor connection in the B CAN-L wire between the windshield wiper control unit and the gauge control module.

    NO 

    An open or poor connection in the B CAN-H wire between the windshield wiper control unit and the gauge control module.

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