Acura B2970: Climate Control Unit Lost Communication with Relay Control Module (RM message)
Is your scanner showing Acura B2970?
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Acura B2970: Climate Control Unit Lost Communication with Relay Control Module (RM message)
OVERVIEWWhat Does The Acura B2970 Code Mean?
Poor communication between the Relay Control Module and the Climate Control Unit.
NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in the B-CAN system diagnosis test mode A. If any of the following DTCs are indicated; B1005, B1959, B2162 or B1158, perform the relay control module input test. If no additional codes are present, perform the climate control unit troubleshooting.
What Are The Potential Causes Of The Acura B2970 Code?
- Loose wire or poor connection on the climate control unit connector A (40P)
- Poor ground (G302)
- Blown fuse in the main under-hood fuse box
- Blown fuse in the under-dash fuse/relay box
- “Open” circuit between the climate control unit and body ground
- “Open” circuit between the MICU and the climate control unit
- Faulty Climate Control Unit
- Faulty Gauge Control Module
Recommended Parts
Below are some recommended auto parts to help you address the trouble code affecting your vehicle and get it running smoothly again:
>>> WORKPRO 582-piece Crimp Terminals, Wire Connectors, Heat Shrink Tube, Electrical Repair Kit
>>> Acura Climate Control Unit
>>> Acura Gauge Control Module
Note: During the purchasing process, please check carefully whether the part you want to buy fits your car!
Reference Sources
2007-2009 Acura MDX HVAC Climate Control Service Manual for B2970 – Pages 109-110.
