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DTC B12A1: Power Control Unit Internal (CPU) Error

WARNING: This page is about a different car, the 2010 Acura TL and 2009 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.
  1. Do the battery terminal disconnect procedure (see BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
  2. Wait for at least 10 seconds to clear the DTCs.
  3. Do the battery terminal reconnection procedure (see BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
  4. Press and hold the engine start/stop button.
  5. Wait for at least 10 seconds.
  6. Check for DTCs with the HDS.

    Is DTC B12A1 indicated? 

    YES  -Replace the power control unit (see POWER CONTROL UNIT  ).

    NO  -Intermittent failure, the system is OK at this time.