What it means
The motor electronics coolant temperature sensor C reports a range/performance condition. Power electronics cooling cannot be regulated reliably.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Motor electronics coolant temperature sensor C reports coolant temperature to the module managing power electronics cooling. P2BDD sets when Sensor C’s signal is plausible as a circuit input but its value is outside the expected range or does not track conditions as expected.
Common causes
Most likely first.
- Sensor characteristic drifted
- Sensor mounting displaced
- Sensor element aged beyond calibration window
Symptoms
- Check-engine light
- Power electronics or hybrid-system warning
- Reduced power or limited operating mode
How to diagnose it
- Review freeze-frame data and related codes to see Sensor C’s reported temperature and the operating conditions when its range/performance fault set.
- After a cold soak, compare Sensor C’s scan-tool reading with ambient conditions and other available coolant temperature readings for an offset.
- Inspect Sensor C’s mounting and coolant contact using the manufacturer's service information, since displacement can make its reading unrepresentative.
- Check Sensor C’s connector and harness for looseness, corrosion, or damage that could affect readings without causing a clear circuit fault.
- If mounting and wiring are sound, test Sensor C’s response as coolant temperature changes against the manufacturer's specification.
Common fixes
- Reposition and secure Sensor C so it measures coolant as intended.
- Repair a poor connection or damaged wiring affecting Sensor C’s signal.
- Replace Sensor C if its temperature response is outside the manufacturer's specification.
Can I keep driving?
Stop safely if the vehicle warns of power electronics overheating or limits power; an inaccurate Sensor C reading can interfere with cooling control. If no such warning is present, limit driving and arrange diagnosis soon.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.