DTC B12C5: Power Switch Failure

DTC (Power Control Unit)

NOTE:  If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A - Refer to: BODY ELECTRICAL TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A - INITIAL COMMUNICATION AND DTC CHECKS .

1. Problem verification

   - 1. Clear the DTCs with the HDS.

   - 2. Press the power button at least 20 times, then wait for at least 20 seconds.

   - 3. Check for DTCs with the HDS.

   DTC Description	DTC
   B12C5: Power Switch Failure

   Is DTC B12C5 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 (+B SMART line, GND line or Power switch, Keyless access control unit)

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

   - 2. Disconnect the following connector.

   POWER SWITCH 10P CONNECTOR

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

   Test condition	Vehicle OFF (LOCK) mode Power switch 10P connector: disconnected
   Test circuit	+B SMART, GND
   Test point 1	Power switch 10P connector No. 5 (RED)
   Test point 2	Power switch 10P connector No. 2 (BLK)

   Courtesy of HONDA, U.S.A., INC.

   Is there battery voltage?

   YES 

   The +B SMART wire is OK. Go to step 3.

   NO 

   Go to step 6.

3. Shorted wire check (SS2 (-), SS1 (+) lines)

   - 1. Disconnect the following connector.

   KEYLESS ACCESS CONTROL UNIT CONNECTOR B (28P)

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

   Test condition	Vehicle OFF (LOCK) mode Power switch 10P connector: disconnected Keyless access control unit connector B (28P): disconnected
   Test circuit	SS2 (-)
   Test point 1	Power switch 10P connector No. 1 (GRN)
   Test point 2	Body ground

   Test circuit	SS1 (+)
   Test point 1	Power switch 10P connector No. 4 (BLU)
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   Repair short to ground in the wire.

   NO 

   The SS2 (-) and SS1 (+) wires are not shorted. Go to step 4.

4. Open wire check (SS2 (-), SS1 (+) lines)

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

   Test condition	Vehicle OFF (LOCK) mode Power switch 10P connector: disconnected Keyless access control unit connector B (28P): disconnected
   Test circuit	SS2 (-)
   Test point 1	Power switch 10P connector No. 1 (GRN)
   Test point 2	Keyless access control unit connector B (28P) No. 8 (GRN)

   Test circuit	SS1 (+)
   Test point 1	Power switch 10P connector No. 4 (BLU)
   Test point 2	Keyless access control unit connector B (28P) No. 12 (BLU)

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The SS2 (-) and SS1 (+) wires are OK. Go to 5.

   NO 

   Repair an open or high resistance in the wire.

5. Power switch operation check

   - 1. Do the power switch test.

   Is the power switch OK?

   YES 

   REPLACE THE KEYLESS ACCESS CONTROL UNIT .

   NO 

   REPLACE THE POWER SWITCH .

6. Open wire check (+B SMART line)

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

   Test condition	Vehicle OFF (LOCK) mode
   Test circuit	+B SMART
   Test point 1	Power switch 10P connector No. 5 (RED)
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there battery voltage?

   YES 

   Repair an open or high resistance in the ground wire or poor ground (G501).

   NO 

   Repair an open or high resistance in the wire.