U0301
Software Incompatibility with ECM/PCM
A control module has detected that its software/calibration is incompatible with the engine ECM/PCM. Typically appears after a partial flash, mismatched coding, or fitting a used ECM from a different vehicle.
A control module has detected that its software/calibration is incompatible with the engine ECM/PCM. Typically appears after a partial flash, mismatched coding, or fitting a used ECM from a different vehicle.
Common causes
- high
Software/calibration mismatch with ECM
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-880
- medium
Used ECM from different vehicle fitted
A plausible cause — test and verify before replacing parts.
Typical part cost: $90-880
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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 U0301 mean?
U0301 means "Software Incompatibility with ECM/PCM". It is a generic OBD-II code that points to a fault in the network / communication.
What are the most common causes of U0301?
software/calibration mismatch with ecm; used ecm from different vehicle fitted; gateway module routing can messages incorrectly — 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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