U02AB
Lost Communication With Vehicle Thermal Management Control Module
The vehicle bus reports loss of communication with the vehicle thermal management module. Coordination of engine, battery and cabin cooling/heating loops is lost; sub-modules fall back to local control.
The vehicle bus reports loss of communication with the vehicle thermal management module. Coordination of engine, battery and cabin cooling/heating loops is lost; sub-modules fall back to local control.
Common causes
- high
Bus wiring open or shorted
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1980
- medium
Module without power or ground
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-1980
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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 U02AB mean?
U02AB means "Lost Communication With Vehicle Thermal Management Control Module". It is a generic OBD-II code that points to a fault in the network / communication.
What are the most common causes of U02AB?
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?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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