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DTC B12C5

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DTC B12C5  : Engine Start/Stop Switch Failure

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

DTC Description DTC
B12C5 Engine start/stop switch failure  

DTC (Power Control Unit)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Press the engine start/stop button at least 20 times, then wait for at least 20 seconds.

    -3. Check for DTCs with the HDS.

    DTC Description DTC
    B12C5 Engine start/stop 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 or GND line, Other)

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

    -2. Disconnect the following connector.

    Engine start/stop switch 10P connector

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

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 10P connector: disconnected
    Test point 1 Engine start/stop switch 10P connector (female terminals) No. 5:
    Test point 2 Engine start/stop switch 10P connector (female terminals) No. 1:
    GHH396393Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

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

    NO 

    Go to step 6.

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

    -1. Disconnect the following connector.

    Body control module connector C (66P)

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

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 10P connector: disconnected
    Body control module connector C (66P): disconnected
    Test point 1 Engine start/stop switch 10P connector (female terminals) No. 6:
    Test point 2 Body ground
    Test point 1 Engine start/stop switch 10P connector (female terminals) No. 10:
    Test point 2 Body ground
    GHH396396Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair short to ground in the wire.

    NO 

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

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

    -1. Connect terminals A and B with a jumper wire.

    Terminal A Body control module connector C (66P) No. 63
    Terminal B Body control module connector C (66P) No. 5

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

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 10P connector: disconnected
    Body control module connector C (66P): disconnected
    Test point 1 Engine start/stop switch 10P connector (female terminals) No. 6:
    Test point 2 Engine start/stop switch 10P connector (female terminals) No. 10:
    GHH396399Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

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

    NO 

    Repair an open or high resistance in the wire.

  5. Engine start/stop switch check

    -1. Do the engine start/stop switch test .

    Is the engine start/stop switch OK?

    YES 

    Replace the body control module .

    NO 

    Replace the engine start/stop switch .

  6. Open wire check (+B SMART line)

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

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 10P connector: disconnected
    Test point 1 Engine start/stop switch 10P connector (female terminals) No. 5:
    Test point 2 Body ground
    GHH396401Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Repair an open or high resistance in the GND wire.

    NO 

    Repair an open or high resistance in the +B SMART wire.