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DTC B12C5

DTC B12C5  : Engine start/stop switch failure

DTC Description DTC
B12C5 Engine start/stop 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 .

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    Clear DTCs

    -2. Press the engine start/stop switch at least twenty 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, SSB GND line, or other)

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

    -2. Disconnect the following connectors.

    Keyless access/TPMS control unit connector B (36P)
    Engine start/stop switch 12P connector

    -3. Connect terminals A and B with a jumper wire.

    Terminal A Keyless access/TPMS control unit connector B (36P) No. 25
    Terminal B Body ground

    -4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 12P connector: disconnected
    Keyless access/TPMS control unit connector B (36P): disconnected
    Test point 1 Engine start/stop switch 12P connector (female terminals) No. 12:
    Test point 2 Engine start/stop switch 12P connector (female terminals) No. 1:
    GHH457667Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The +B SMART and SSB GND wires are OK. Go to step 3.

    NO 

    Go to step 6.

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

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

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 12P connector: disconnected
    Keyless access/TPMS control unit connector B (36P): disconnected
    Test point 1 Engine start/stop switch 12P connector (female terminals) No. 6:
    Test point 2 Body ground
    Test point 1 Engine start/stop switch 12P connector (female terminals) No. 7:
    Test point 2 Body ground
    GHH457670Courtesy 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.

    Test condition Vehicle OFF (LOCK) mode
    Engine start/stop switch 12P connector: disconnected
    Keyless access/TPMS control unit connector B (36P): disconnected
    Test point 1 Engine start/stop switch 12P connector (female terminals) No. 6:
    Test point 2 Keyless access/TPMS control unit connector B (36P) No. 11
    Test point 1 Engine start/stop switch 12P connector (female terminals) No. 7:
    Test point 2 Keyless access/TPMS control unit connector B (36P) No. 10
    GHH457673Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The SS2- and SS1+ 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 keyless access/TPMS control unit .

    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 12P connector: disconnected
    Keyless access/TPMS control unit connector B (36P): disconnected
    Test point 1 Engine start/stop switch 12P connector (female terminals) No. 12:
    Test point 2 Body ground
    GHH457675Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Repair an open or high resistance in the SSB GND wire.

    NO 

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