P0CD7Hybrid/EV Battery Pack Coolant Temperature Sensor B Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0CD7 reports that the signal of battery coolant temperature sensor B at the pack outlet has dropped toward ground. On an NTC thermistor with pull-up resistor a low voltage reads as very hot coolant, so a short to ground or a damaged sensor is the usual explanation rather than real overheating. GM's battery energy control module in the 2011 Chevrolet Volt and 2016 Cadillac ELR stores the code once the outlet value reaches 87.9 °C, an ADC count of 130 or less, for 1.75 s within a 2.5 s window; it is rated Type B, so the MIL lights after the second trip. While it is active, GM suspends the outlet plausibility test P0CD6 and the coolant pump checks that rely on this value. Expect reduced charging or power until the signal is back. The open-circuit counterpart is P0CD8, sensor A low is P0C44.
- What you may notice
- MIL on after two trips (GM)
- Displayed outlet coolant temperature implausibly high
- Charging or drive power reduced
- Likely causes
- LikelySignal wire of sensor B shorted to ground
- PossibleSensor B internally shorted or water-damaged
- RareInput stage of the battery control module faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €60 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.