DTC B1901: Backup Control Unit Internal Error (CPU Error (2013-18)

DTC (Backup Control Unit)

1. Problem verification:

   Do the battery terminal disconnection procedure .

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

   - 3. Do the battery terminal reconnection procedure .

   - 4. Push the door outer handle door lock button to lock the door.

   - 5. Touch the door outer handle touch sensor to unlock the door.

   - 6. Connect the HDS to the data link connector (DLC) - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2013-15), or How to Troubleshoot the A/T System (2013-15), or How to Troubleshoot the Fuel and Emissions Systems (2016-18), or How to Troubleshoot the A/T System (2016-18) .

   - 7. Press the engine start/stop button to select the ON mode according to the instructions on the HDS screen.

   - 8. Check for DTCs with the HDS.

   DTC Description	DTC
   B1901 Backup Control Unit Internal Error (CPU Error)

   Is DTC B1901 indicated?

   YES 

   Replace the backup control unit .

   NO 

   Intermittent failure, the system is OK at this time.