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Home >> Acura >> 2008 >> MDX >> Repair and Diagnosis >> Electrical >> Motors, Switches, Relays >> Under-Hood Fuse/Relay Box >> DTC Troubleshooting >> DTC B1055: Relay Control Module Lost Communication with MICU (MICU Message); DTC B1056: Relay Control Module Lost Communication with MICU (ALARM Message); DTC B1057: Relay Control Module Lost Communication with MICU (DOOR SW Message)
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DTC B1055: Relay Control Module Lost Communication with MICU (MICU Message); DTC B1056: Relay Control Module Lost Communication with MICU (ALARM Message); DTC B1057: Relay Control Module Lost Communication with MICU (DOOR SW Message)

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 ON (II).
  3. Wait for 6 seconds or more.
  4. Check for DTCs with the HDS.

    Is DTC B1055, B1056, or B1057 indicated? 

    YES  - Go to step 5.

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

  5. Check for DTCs with the HDS.

    Are DTCs B1055, B1056, B1057, B1157, B1159, B1180, B1255, B1955, B2155, B2156, and B2161 all indicated? 

    YES  - Do the MICU input test (see MICU INPUT TEST ).

    NO  - Do the relay control module input test (see RELAY CONTROL MODULE INPUT TEST ).