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B1056

DTC B1056: Relay Control Module Lost Communication with MICU (ALARM 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 B1056 indicated?

YES - Go to relay control module input test. Relay Control Module Input Test

NO - Intermittent failure, the relay control module system is OK at this time. Check for loose or poor connections.