P0CD8 code meaning
Hybrid/EV Battery Pack Coolant Temperature Sensor B Circuit High
Powertrain system Generic code P0Cxx codes Check engine light
What P0CD8 means
P0CD8 is the high-voltage fault of battery coolant temperature sensor B at the pack outlet. On the usual NTC circuit the signal rises to the reference when the loop is broken, so the controller sees an impossible temperature below -40 °C. The battery energy control modules of the 2011 Chevrolet Volt and 2016 Cadillac ELR use exactly this limit, an ADC count above 3823, held for 1.75 s within 2.5 s; the code is Type B with the MIL on the second trip. Connectors left unplugged after work on the battery, corroded pins, a broken wire or a short to a supply line are the common findings, an open sensor element is rarer. Until it is fixed the battery may not be heated or cooled as intended and cold-weather power can be limited. The low counterpart is P0CD7, sensor A high is P0C45.
P0CD8 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0CD8
- MIL on after two trips (GM)
- Outlet coolant temperature shows about -40 °C
- Limited power or charging in cold weather
Common causes of P0CD8
- Most likelyConnector of sensor B unplugged or not latched after service
- PossibleBroken signal or ground wire, corroded terminals
- Less likelySignal wire shorted to a voltage source
- Less likelySensor element internally open
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery pack coolant temp sensor bWiring harnessBms
What each part of P0CD8 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| C | Area: hybrid propulsion. |
| D8 | The exact fault in that area. |
What to do next
- Note P0CD8 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0CD8
What does P0CD8 mean?
P0CD8 means "Hybrid/EV Battery Pack Coolant Temperature Sensor B Circuit High". P0CD8 is the high-voltage fault of battery coolant temperature sensor B at the pack outlet. It is a generic code, so it means the same on every make.
Is it safe to drive with P0CD8?
Drive gently and only to a workshop. With P0CD8 the car can go into limp mode (reduced power) to protect itself.
Will P0CD8 fail an emissions test?
Yes, it can. P0CD8 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0CD8 to fix?
Difficulty: hard. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P0CD8 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.