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DTC B1040

DTC B1040  : BCM lost communication with Front wiper

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
DTC Description DTC
B1040 BCM lost communication with Front wiper  

DTC (Body Control Module)

  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
    B1040 BCM lost communication with Front wiper  

    Is DTC B1040 indicated?

    YES 

    Go to step 2.

    NO 

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

  2. Fuse check

    -1. Check the following fuse.

    Fuse No. B2-5

    Is the fuse OK?

    YES 

    Go to step 3.

    NO 

    Replace the fuse. If the fuse blows again, repair a short to ground in the No. B2-5 fuse circuit.

  3. Determine possible failure area (+B WIPER/GND line, LIN(FR WIPER) line)

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

    -2. Disconnect the following connector.

    Driver's windshield wiper control unit/motor 5P connector

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

    Test condition Vehicle OFF (LOCK) mode
    Driver's windshield wiper control unit/motor 5P connector: disconnected
    Test point 1 Driver's windshield wiper control unit/motor 5P connector No. 3
    Test point 2 Driver's windshield wiper control unit/motor 5P connector No. 1

    Is there battery voltage?

    YES 

    Go to step 5.

    NO 

    Go to step 4.

  4. Open wire check (+B WIPER line)

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

    Test condition Vehicle OFF (LOCK) mode
    Driver's windshield wiper control unit/motor 5P connector: disconnected
    Test point 1 Driver's windshield wiper control unit/motor 5P connector No. 3
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Repair an open or high resistance in the wire between the driver's windshield wiper control unit/motor and body ground or poor ground (G205).

    NO 

    Repair an open or high resistance in the wire.

  5. Shorted wire check (LIN(FR WIPER) line)

    -1. Disconnect the following connector.

    Body control module connector C (28P)

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (28P): disconnected
    Driver's windshield wiper control unit/motor 5P connector: disconnected
    Test point 1 Driver's windshield wiper control unit/motor 5P connector No. 5
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

    The LIN(FR WIPER) wire is not shorted. Go to step 6.

  6. Open wire check (LIN(FR WIPER) line)

    -1. Disconnect the following connectors.

    Washer motor control unit connector A (6P)

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (28P): disconnected
    Driver's windshield wiper control unit/motor 5P connector: disconnected
    Washer motor control unit A (6P): disconnected
    Test point 1 Driver's windshield wiper control unit/motor 5P connector No. 5
    Test point 2 Body control module connector C (28P) No. 13

    Is there continuity?

    YES 

    The LIN(FR WIPER) wire is OK. Replace the driver's windshield wiper control unit/motor .

    NO 

    An open or poor connection in the wire.