DTC Troubleshooting: B1040
DTC B1040: BCM (Body Control Module) 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 (Body Control Module) Lost Communication with Front Wiper
  

1.
Problem verification:

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 (Body Control Module) 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:

Fuse check
?1.
Check the following fuse.
Fuse
No. A2-5 (30 A)
Location
Under-hood fuse/relay box

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. A2-5 (30 A) fuse circuit.?
3.
Determine possible failure area (windshield wiper control unit/motor power and ground, LIN(FR WIPER) line):

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 5.
     
NO
     
     
     
Go to step 4.
4.
Open wire check (+B WIPER line):

Open wire check (+B WIPER line)
?1.
Check for continuity 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 (G302).?
     
NO
     
     
     
Repair an open or high resistance in the wire.?
5.
Shorted wire check (LIN(FR WIPER) line):

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
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 continuity?

     
YES
     
     
     
Repair a short to ground in the LIN(FR WIPER) wire between the body control module and the windshield wiper control unit/motor.?
     
NO
     
     
     
The LIN(FR WIPER) wire is not shorted. Go to step 6.
6.
Open wire check (LIN(FR WIPER) line):

Open wire check (LIN(FR WIPER) line)
?1.
Check for continuity 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 continuity?

     
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 LIN(FR WIPER) wire between the body control module and the windshield wiper control unit/motor.?