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DTC U0199 (Keyless Access Control Unit)

DTC U0199  : Keyless Access Control Unit - Door Multiplex Control Unit Communication Error

DTC Description DTC
U0199 Keyless Access Control Unit - Door Multiplex Control Unit Communication Error  

DTC (Keyless Access 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
    U0199 Keyless Access Control Unit - Door Multiplex Control Unit Communication Error  

    Is DTC U0199 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 (power window master switch 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 POWER WINDOW UNIT.

    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. D26 (7.5 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. D26 (7.5 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.

    Power window master switch 37P connector

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

    Test condition Vehicle OFF (LOCK) mode
    Power window master switch 37P connector: disconnected
    Test circuit +B BACK UP
    Test point 1 Power window master switch 37P connector No. 26 (PNK)
    Test point 2 Body ground
    GHH348747Courtesy 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 (IG2 A/C line)

    -1. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
    Power window master switch 37P connector: disconnected
    Test circuit IG2 A/C
    Test point 1 Power window master switch 37P connector No. 25 (LT GRN)
    Test point 2 Body ground
    GHH348748Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The IG2 A/C 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
    Power window master switch 37P connector: disconnected
    Test circuit GND
    Test point 1 Power window master switch 37P connector No. 3 (BRN)
    Test point 2 Body ground
    Test circuit GND
    Test point 1 Power window master switch 37P connector No. 31 (BRN)
    Test point 2 Body ground
    GHH348749Courtesy 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 (G502).

  7. Open wire check (B CAN lines)

    -1. Disconnect the following connector.

    Keyless access control unit connector B (28P)

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

    Test condition Vehicle OFF (LOCK) mode
    Power window master switch 37P connector: disconnected
    Keyless access control unit connector B (28P): disconnected
    Test circuit B CAN-H
    Test point 1 Power window master switch 37P connector No. 28 (RED)
    Test point 2 Keyless access control unit connector B (28P) No. 6 (RED)
    GHH348750Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    An open or poor connection in the B CAN-L wire between the keyless access control unit and the power window master switch.

    NO 

    An open or poor connection in the B CAN-H wire between the keyless access control unit and the power window master switch.

  8. Open wire check (B CAN lines)

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

    -2. Disconnect the following connectors.

    Power window master switch 37P connectorKeyless access control unit connector B (28P)

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

    Test condition Vehicle OFF (LOCK) mode
    Power window master switch 37P connector: disconnected
    Keyless access control unit connector B (28P): disconnected
    Test circuit B CAN-H
    Test point 1 Power window master switch 37P connector No. 28 (RED)
    Test point 2 Keyless access control unit connector B (28P) No. 6 (RED)
    GHH348751Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    An open or poor connection in the B CAN-L wire between the keyless access control unit and the power window master switch.

    NO 

    An open or poor connection in the B CAN-H wire between the keyless access control unit and the power window master switch.

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