P0CBFDrive Motor A Coolant Temperature Sensor Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0CBF is the code for an excessive signal from the coolant temperature sensor of drive motor A. With an NTC element a very high resistance stands for extreme cold, so in practice an open sensor, a broken wire or a disconnected plug is behind it. In GM's 2013 eAssist table 13OBDG05C the code is set when the raw value exceeds 176,962 Ω, the equivalent of −40 °C, in 50 of 62 samples at 100 ms with ignition in run/crank, Type B, two trips. Because −40 °C is a real if rare ambient temperature, the check uses a resistance far beyond the normal working curve. With the loop temperature unknown, the system has to fall back on substitute values and may scale back the electric assist. The codes P0CBD and P0CC2 rely on this sensor and are blocked while P0CBF is present; P0CBE is its low counterpart.
- What you may notice
- Check-engine lamp after two trips
- Coolant temperature of the motor shown at minimum value
- Likely causes
- LikelyOpen signal or return wire, or unplugged sensor
- PossibleSensor element open internally
- RareCorroded pins at sensor or control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.