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 .
• Before troubleshooting, make sure the fuses and relays associated with the system is OK.

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. Determine possible failure area (windshield wiper control unit/motor power and ground, LIN(FR_WIPER) line)

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

   -2. Disconnect the following connector.

   Windshield wiper control unit/motor 6P connector

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

   Test condition	Vehicle OFF (LOCK) mode Windshield wiper control unit/motor 6P connector: disconnected
   Test point 1	Windshield wiper control unit/motor 6P connector No. 2
   Test point 2	Windshield wiper control unit/motor 6P connector No. 1

   Is there battery voltage?

   YES 

   Go to step 4.

   NO 

   Go to step 3.

3. Open wire check (+B_WIPER line)

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

   Test condition	Vehicle OFF (LOCK) mode Windshield wiper control unit/motor 6P connector: disconnected
   Test point 1	Windshield wiper control unit/motor 6P connector No. 2
   Test point 2	Body ground

   Is there battery voltage?

   YES 

   Repair an open or high resistance in the ground wire or poor ground (G351).

   NO 

   Repair an open or high resistance in the wire.

4. Shorted wire check (LIN(FR_WIPER) line)

   -1. Disconnect the following connector.

   Body control module connector C (28P)

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

   Test condition

   Vehicle OFF (LOCK) mode Body control module connector C (28P): disconnected Windshield wiper control unit/motor 6P connector: disconnected

   Test point 1	Windshield wiper control unit/motor 6P connector No. 4
   Test point 2	Body ground

   Is there 1.0 MΩ or more?

   YES 

   The LIN(FR_WIPER) wire is not shorted. Go to step 5.

   NO 

   Repair a short to ground in the wire.

5. Open wire check (LIN(FR_WIPER) line)

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

   Test condition	Vehicle OFF (LOCK) mode Body control module connector C (28P): disconnected Windshield wiper control unit/motor 6P connector: disconnected
   Test point 1	Body control module connector C (28P) No. 13
   Test point 2	Windshield wiper control unit/motor 6P connector No. 4

   Is there 1.0 Ω or less?

   YES 

   The LIN(FR_WIPER) wire is OK. Replace the windshield wiper control unit/motor . If the DTC is still present, replace the body control module .

   NO 

   An open or poor connection in the wire.