PCM/ECM/TCM Internal Temperature Sensor Circuit High
Common Symptoms
- Check Engine Light illuminated
- Transmission may enter limp mode or default shift pattern
- Hard or delayed shifting
- Reduced engine performance or power limitation
- Transmission overheat warning message displayed
Most Likely Root Causes
- Failed PCM/ECM/TCM internal temperature sensor
- Faulty powertrain control module
- Internal control module circuit fault
- Corrosion or moisture inside control module
- Control module software or calibration issue
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Component Location
The PCM/ECM/TCM is typically mounted in the engine compartment on the firewall, inner fender, or under the dashboard near the center console.
Manufacturer Notes
This code indicates an internal sensor fault within the control module itself and may require module replacement or reprogramming depending on manufacturer.
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