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B1012

DTC B1012: MICU Lost Communication with the MICU-Rear Junction Box (RJU Message)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.

1. Clear the DTCs with the HDS.
2. Turn the ignition switch OFF, and then back ON (II).
3. Wait for 6 seconds or more.
4. Check for DTCs with the HDS.

Is DTC B1012 indicated?

YES - Go to step 5.

NO - Intermittent failure, the MICU-rear junction box is OK at this time. Check for loose or poor connection at the MICU-rear junction box connector A (14P), and at the driver's under-dash fuse/relay box connector G (6P). If the connections are good, check the battery condition and the charging system.

5. Check for DTCs with the HDS.

Is DTC B2007 also indicated?

YES - Go to the MICU-rear junction box input test. Component Tests and General Diagnostics

NO - Check for an open in the communication circuit between the MICU and the MICU-rear junction box. If the circuit is OK, replace the MICU. If the circuit is bad, repair the open.