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Home >> Acura >> 2012 >> MDX >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Immobilizer System >> DTC Troubleshooting >> DTC B1901: Immobilizer Unit Internal Error (CPU error); DTC B1902: Immobilizer Unit Internal Error (EEPROM error)
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DTC B1901: Immobilizer Unit Internal Error (CPU error); DTC B1902: Immobilizer Unit Internal Error (EEPROM error)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch to LOCK (0) and then back to ON (II).
  3. Check for DTCs with the HDS.

    Are DTC B1901 and/or B1902 indicated? 

    YES  -Faulty immobilizer-keyless control unit, replace the immobilizer-keyless control unit (see IMMOBILIZER-KEYLESS CONTROL UNIT REPLACEMENT  ).

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