U0661
Lost Communication With Right Rear Temperature Actuator A
The vehicle bus reports loss of communication with smart right-rear HVAC temperature blend door actuator A. Rear-right air temperature falls back to a default position.
The vehicle bus reports loss of communication with smart right-rear HVAC temperature blend door actuator A. Rear-right air temperature falls back to a default position.
Common causes
- high
Bus wiring open or shorted
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-660
- medium
Module without power or ground
A plausible cause — test and verify before replacing parts.
Typical part cost: $90-660
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does U0661 mean?
U0661 means "Lost Communication With Right Rear Temperature Actuator A". It is a generic OBD-II code that points to a fault in the network / communication.
What are the most common causes of U0661?
bus wiring open or shorted; module without power or ground; module failed — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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