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DTC B12D2: Power control unit IG2 circuit error

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DTC Description DTC
B12D2 Power control unit IG2 circuit error  

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 .

NOTE:  Make sure aftermarket accessories are not installed.

  1. Problem verification:

    - 1. Turn the vehicle to the ON mode.

    - 2. Clear the DTCs with the HDS.

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

    - 4. Wait 10 seconds.

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

    - 6. Wait 5 seconds.

    - 7. Turn the vehicle to the ON mode.

    - 8. 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.

  2. Determine possible failure area (IG2 relay circuit ON problem, IG2 relay circuit OFF problem):

    - 1. Select KEYLESS ACCESS CONTROL from the ONE-PUSH START system select menu with the HDS, and enter DATA LIST.

    One-Push - KEYLESS ACCESS CONTROL UNIT - DATA LIST

    - 2. Check the IG2 with the HDS.

    Is there battery voltage?

    YES 

    Go to step 3.

    NO 

    Go to step 4.

  3. Under-dash subrelay box test (IG2 relay circuit):

    Do the under-dash subrelay box test (IG2 relay circuit) .

    Is IG1a relay circuit OK?

    YES 

    Repair a short to power in the IG2 SIG wire.

    NO 

    Faulty IG2 relay circuit, replace the under-dash subrelay box .

  4. Under-dash subrelay box test (IG2 relay circuit):

    Do the under-dash subrelay box test (IG2 relay circuit) .

    Is IG2 relay circuit OK?

    YES 

    Repair an open or high resistance in the IG2 SIG wire.

    NO 

    Faulty IG2 relay circuit, replace the under-dash subrelay box .