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Home >> Acura >> 2007 >> RDX >> Repair and Diagnosis >> External Pages >> Different car >> Section 1321 (Rear Fuse/Relay Box) >> DTC Troubleshooting >> DTC B1957: Rear MICU Lost Communication with Combination Switch Control Unit (HLSW Message); DTC B1958: Rear MICU Lost Communication with Combination Switch Control Unit (WIPSW Message)
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DTC B1957: Rear MICU Lost Communication with Combination Switch Control Unit (HLSW Message); DTC B1958: Rear MICU Lost Communication with Combination Switch Control Unit (WIPSW Message)

WARNING: This page is about a different car, the 2009 Acura MDX, 2008 Acura MDX, and 2007 Acura MDX. 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 ).
  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 B1957 and/or B1958 indicated? 

    YES  - Go to step 5.

    NO  - Intermittent failure, the system is OK at this time. Check for loose or poor connections between the rear MICU and the combination switch control unit.

  5. Check for DTCs with the HDS.

    Are DTCs B1007, B1062, B1063, B1155, B1156, B1957, B1958, and/or B2969 all indicated? 

    YES  - Do the combination switch control unit input test (see WIPER/WASHER SWITCH (COMBINATION SWITCH CONTROL UNIT) INPUT TEST ).

    NO  - Do the rear MICU input test (see REAR MICU INPUT TEST ).