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DTC B12D2

DTC B12D2  : Power Control Unit IG2 Circuit Error

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

DTC Description DTC
B12D2 Power Control Unit IG2 Circuit Error  

DTC (Power Control Unit)

NOTE:  Make sure aftermarket accessories are not installed.

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the ON mode.

    -3. Wait for 10 seconds.

    -4. Turn the vehicle to the OFF (LOCK) mode.

    -5. Wait for 5 seconds.

    -6. Check for DTCs with the HDS.

    DTC Description DTC
    B12D2 Power Control Unit IG2 Circuit Error  

    Is DTC B12D2 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 (IG2 relay circuit ON problem, IG2 relay circuit OFF problem)

    -1. Turn the vehicle to the ON mode.

    -2. Check the parameter (s) below with the HDS.

    Signal Current conditions
    Value Unit
    IG2    

    -3. Check the IG2 with the HDS.

    Is there battery voltage?

    YES 

    Repair a short to power in the wire or faulty IG2 relay circuit, replace the under-dash fuse/relay box .

    NO 

    Repair an open or high resistance in the wire or faulty IG2 relay circuit, replace the under-dash fuse/relay box .