P0668
PowertrainPcm Internalmoderate severityPCM/ECM/TCM Internal Temperature Sensor Circuit Low
What P0668 Means
The PCM detected a low voltage signal from the internal module temperature sensor. This sensor monitors the control module's internal temperature.
Symptoms
- Check engine light on
- Possible performance issues
- No obvious drivability symptoms
Common Causes
- Faulty internal temperature sensor
- Internal circuit fault
- Overheated control module
- Faulty PCM
Diagnostic Steps
- Scan for codes
- Verify sensor data with scan tool
- Check module for heat exposure
- Replace PCM if internal fault confirmed
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✓ Autel official store
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