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Home >> Honda >> 2014 >> Accord Plug-In >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 110 (Keyless Access Power Control Unit - Diagnostics (Except Hybrid)) >> DTC Troubleshooting >> DTC B12D2: Power Control Unit IG2 Circuit Error
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DTC B12D2: Power Control Unit IG2 Circuit Error

WARNING: This page is about a different variant/trim than selected.
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. Press the engine start/stop button to select the ON mode.

    - 3. Wait 10 seconds.

    - 4. Press the engine start/stop button to select the OFF mode.

    - 5. Wait 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 below.

    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. Press the engine start/stop button to select the ON mode

    - 2. 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

    - 3. Check the IG2 with the HDS.

    Is there battery voltage?

    YES 

    Go to step 3 below.

    NO 

    Go to step  4

  3. Under-dash sub fuse/relay box test (IG2 relay circuit)

    -1. Do the under-dash sub relay box test (IG2 relay circuit).

    Is IG1a relay circuit OK?

    YES 

    Repair a short to power in the wire.

    NO 

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

  4. Under-dash sub fuse/relay box test (IG2 relay circuit)

    -1. Do the under-dash sub relay box test (IG2 relay circuit).

    Is IG2 relay circuit OK?

    YES 

    Repair an open or high resistance in the wire.

    NO 

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