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DTC B12F0

DTC B12F0  : Power Control Unit Lost Communication with Electric Steering Lock

NOTE: 

DTC Description DTC
B12F0 Power Control Unit Lost Communication with Electric Steering Lock  

DTC (Keyless Access Power Control Unit)

  1. Problem verification 1

    -1. Clear the DTCs with the HDS.

    -2. Do this procedure ten times: Press the engine start/stop switch to select the OFF (LOCK), ACCESSORY, ON, and OFF (LOCK) mode.

    -3. Check for DTCs with the HDS.

    DTC Description DTC
    B12F0 Power Control Unit Lost Communication with Electric Steering Lock  

    Is DTC B12F0 indicated?

    YES 

    Go to step 2.

    NO 

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

  2. Open wire check (+B SMART line)

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

    -2. Disconnect the following connector.

    Electric steering lock 12P connector

    -3. Measure the voltage 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 (female terminals) No. 3:
    Test point 2 Body ground
    GHH429252Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

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

    NO 

    Repair an open or high resistance in the wire.

  3. Open wire check (GND line)

    -1. 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 (female terminals) No. 7:
    Test point 2 Body ground
    GHH429254Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The GND wire is OK. Go to step 4.

    NO 

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

  4. Shorted wire check (IGN TRX line)

    -1. Disconnect the following connector.

    Body control module connector G (32P)

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

    Test condition Vehicle OFF (LOCK) mode Electric steering lock 12P connector: disconnected Body control module connector G (32P): disconnected
    Test point 1 Electric steering lock 12P connector (female terminals) No. 6:
    Test point 2 Body ground
    GHH429256Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

    The IGN TRX wire is not shorted. Go to step 5.

  5. Open wire check (IGN TRX line)

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

    Test condition Vehicle OFF (LOCK) mode Electric steering lock 12P connector: disconnected Body control module connector G (32P): disconnected
    Test point 1 Electric steering lock 12P connector (female terminals) No. 6:
    Test point 2 Body control module connector G (32P) No. 28
    GHH429258Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The IGN TRX wire is OK. Go to step 6.

    NO 

    Repair an open or high resistance in the wire.

  6. Keyless access system check:

    Reconnect these items:

    • Electric steering lock 12P connector
    • Body control module connector G (32P)

    -2. With driver's power window open, turn the vehicle to the OFF (LOCK) mode.

    -3. Do the 12 volt battery terminal disconnection procedure .

    -4. Wait for at least 10 seconds to clear the DTCs.

    -5. Do the 12 volt battery terminal reconnection procedure .

    -6. Turn the vehicle to the ON mode then the OFF (LOCK) mode.

    -7. Remove all the keyless remotes from inside the vehicle. Hold them outside the open driver's window, at least 20 cm (8.0 in) away from the vehicle.

    -8. Close all doors, then press the engine start/stop switch.

    -9. The keyless remotes bring to the vehicle inside, during close all doors.

    -10.

    Touch the engine start/stop switch with the keyless remote. The buttons on the keyless remote should be facing you.

    -11.

    Press the engine start/stop switch, and turn the vehicle to the ON mode.

    Does the mode change to ON?

    YES 

    Go to step 7.

    NO 

    Go to step 8.

  7. Problem verification 2

    -1. Clear the DTCs with the HDS.

    -2. Do this procedure ten times: Press the engine start/stop switch to select the OFF (LOCK), ACCESSORY, ON, and OFF (LOCK) mode.

    -3. Check for DTCs with the HDS.

    DTC Description DTC
    B12F0 Power Control Unit Lost Communication with Electric Steering Lock  

    Is DTC B12F0 indicated?

    YES 

    Replace the electric steering lock .

    NO 

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

  8. Electric steering lock communication status check

    -1. Select COMMUNICATION STATUS in the INSPECTION MENU with the HDS.

    One-Push - KEYLESS ACCESS CONTROL UNIT - STATUS LOG

    Check the value of STATUS with ELECTRICAL STEERING LOCK, STATUS with KEYLESS ACCESS CONTROL UNIT, and STATUS with BACKUP CONTROL UNIT with the HDS.

    One-Push - BACKUP CONTROL UNIT - STATUS LOG

      HDS Description Value
    Status with ESL MTR CUT1 (Cont) Status 1
    MTR CUT2 (IG) Status 1
    IG1 Input State of ESL 1
    MTRCONT Status of ESL 1
    ESL Motor Status 1
    Switch D detection for Unlock Status 1
    Switch C detection for Unlock Status 1
    Switch B detection for Unlock Status 1
    Status with KEYLESS ACCESS CONTROL UNIT FOB KEY Authentication Result 1
    Status with BACKUP CONTROL UNIT FOB KEY Authentication Result 1

    NOTE:  The parameters are displayed only when the vehicle cannot be turned to the ON mode.

    Are only Status with ELECTRICAL STEERING LOCK 1 values indicated?

    YES 

    Replace the electric steering lock .

    NO 

    Replace the body control module .