DTC B1901: Immobilizer Unit Internal Error (CPU Error); DTC B1902: Immobilizer Unit Internal Error (EEPROM Error)

WARNING: This page is about a different car, the 2012 Honda Pilot. However, it is still accessible from the selected car via links, so may be relevant.

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 ).

Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0) and then back to ON (II).
Wait for at least 6 seconds.
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.