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DTC B2970: Climate Control Unit Lost Communication with Relay Control Module (RM 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 the B-can system diagnosis test mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Clear the DTC with the HDS.
  2. Turn the ignition switch to LOCK (0), and then ON (II).
  3. Wait for 6 seconds or more.
  4. Do the self-diagnostic with the HDS (see HOW TO USE THE SELF-DIAGNOSTIC FUNCTION WITH THE HDS  ).
  5. Check the DTCs.

    Is DTC B2970 indicated? 

    YES  - Go to step 6.

    NO  - Intermittent failure, check for loose wire or poor connection on the climate control unit connector A (40P).

  6. Check for DTCs with the HDS.

    Are any of the following DTCs indicated; B1005, B1959, B2162 or B1158 indicated? 

    YES  - Do the relay control module input test (see GAUGE CONTROL MODULE INPUT TEST ).

    NO  - Do the climate control unit troubleshooting (see CLIMATE CONTROL UNIT TROUBLESHOOTING  ).