DTC Troubleshooting: B12C7

DTC B12C7: Electric steering lock motor circuit failure

DTC Description	DTC
B12C7 Electric steering lock motor circuit failure

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

Problem verification:

Problem verification

?1.	Turn the vehicle to the ON mode.

?2.	Clear the DTCs with the HDS.

?3.	Do this procedure 10 times: Turn the vehicle to the OFF (LOCK) mode, ACCESSORY mode, ON mode, and OFF (LOCK) mode.

?4.	Turn the vehicle to the ON mode.

?5.

Check for DTCs with the HDS.

DTC Description	DTC
B12C7 Electric steering lock motor circuit failure

Is DTC B12C7 indicated?


	YES

Go to step 2.


	NO

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

Open wire check (GND line):

Open wire check (GND line)

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

?2.

Disconnect the following connector.

Electric steering lock 12P connector

?3.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode Electric steering lock 12P connector: disconnected
Test point 1	Electric steering lock 12P connector No. 7
Test point 2	Body ground

Is there continuity?


	YES

The GND wire is OK. Go to step 3.


	NO

Repair an open or high resistance in the GND wire or poor ground (G401).?

Shorted wire check (MTR CUT1 (CONT), MTR CUT2 (IG1) lines):

Shorted wire check (MTR CUT1 (CONT), MTR CUT2 (IG1) lines)

?1.

Disconnect the following connector.

Keyless access control unit connector B (36P)

?2.

Check for continuity between test points 1 and 2 individually.

Test condition	Vehicle OFF (LOCK) mode Electric steering lock 12P connector: disconnected Keyless access control unit connector B (36P): disconnected
Test point 1	Electric steering lock 12P connector No. 2
Test point 2	Body ground

Test point 1	Electric steering lock 12P connector No. 4
Test point 2	Body ground

Is there continuity?


	YES

Repair a short to ground in the wire.?


	NO

The MTR CUT1 (CONT) and MTR CUT2 (IG1) wires are not shorted. Go to step 4.

Open wire check (MTR CUT1 (CONT), MTR CUT2 (IG1) lines):

Open wire check (MTR CUT1 (CONT), MTR CUT2 (IG1) lines)

?1.

Check for continuity between test points 1 and 2 respectively.

Test condition	Vehicle OFF (LOCK) mode Electric steering lock 12P connector: disconnected Keyless access control unit connector B (36P): disconnected
Test point 1	Keyless access control unit connector B (36P) No. 6
Test point 2	Electric steering lock 12P connector No. 4

Test point 1	Keyless access control unit connector B (36P) No. 5
Test point 2	Electric steering lock 12P connector No. 2

Is there continuity?


	YES

Faulty electric steering lock, replace the steering lock. If the DTC is still present, replace the keyless access control unit.?


	NO

Repair an open or high resistance in the wire.?