DTC Troubleshooting: B1905
DTC B1905:
 Immobilizer-Keyless Control Unit Lost Communication with MICU (DRLOCKSW Message)
  1. Clear the DTCs with the HDS.
  1. Turn the ignition switch OFF, and then back ON (II).
  1. Wait for 6 seconds or more.
  1. Check for DTCs with the HDS.
Is DTC B1905 indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure, the immobilizer-keyless control unit is OK at this time. Check for loose or poor connections between the immobilizer-keyless control unit and the MICU.■
  1. Check for DTCs with the HDS.
Are DTCs B1155, B1156, B1157, B1159, B1160, and B1188 all indicated with DTC B1905 at the same time?
YES -
Faulty MICU; replace the under-dash fuse/relay box. ■
NO -
Replace the immobilizer-keyless control unit.■