P0C45 code meaning
Hybrid/EV Battery Pack Coolant Temperature Sensor A Circuit High
Powertrain system Generic code P0Cxx codes Check engine light
What P0C45 means
P0C45 indicates that the signal of battery coolant temperature sensor A sits near the reference voltage. On an NTC circuit with pull-up this looks like extreme cold and usually comes from an open circuit, an unplugged connector or a short to voltage. GM uses the code in the battery energy control module: the 2011 Chevrolet Volt fails the test below -40 °C at an ADC count above 3823, the 2019 hybrid tables at a count above 3890. In both cases 1.75 s within 2.5 s are needed, and the Type B rating lights the MIL after two trips. With the inlet reading lost, the controller runs the battery cooling and heating on substitute values and may cut power in hot or cold weather. The low counterpart is P0C44; sensor B reports the same fault as P0CD8.
P0C45 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 P0C45
- MIL after two trips
- Coolant temperature shown at about -40 °C in live data
- Reduced charging power in extreme temperatures
Common causes of P0C45
- Most likelyOpen signal or ground wire, or connector not latched
- PossibleCoolant temperature sensor open internally
- Less likelySignal wire shorted to a voltage source
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 aWiring harnessBms
What each part of P0C45 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. |
| 45 | The exact fault in that area. |
What to do next
- Note P0C45 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 P0C45
What does P0C45 mean?
P0C45 means "Hybrid/EV Battery Pack Coolant Temperature Sensor A Circuit High". P0C45 indicates that the signal of battery coolant temperature sensor A sits near the reference voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with P0C45?
Drive gently and only to a workshop. With P0C45 the car can go into limp mode (reduced power) to protect itself.
Will P0C45 fail an emissions test?
Yes, it can. P0C45 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 P0C45 to fix?
Difficulty: hard. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P0C45 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.