Common Symptoms
- Check Engine Light illuminated
- Engine control module overheating warning
- Intermittent loss of engine power or performance
- Engine may enter limp mode or reduced power mode
- No noticeable drivability issues in some cases
Most Likely Root Causes
- Failed internal temperature sensor in the PCM or ECM
- Corrosion or moisture intrusion inside the control module
- Excessive heat exposure to the control module
- Internal control module circuit failure
- Software or calibration issue in the control module
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Component Location
The PCM or ECM internal temperature sensor is integrated inside the engine control module housing, typically mounted on the firewall or inner fender.
Manufacturer Notes
Some manufacturers have issued updates for internal temperature sensor monitoring logic or control module hardware revisions to address false fault codes.
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