P0CF0 code meaning
Hybrid/EV Electronics Coolant Temperature Sensor A Circuit Low
Powertrain system Generic code P0Cxx codes Check engine light
What P0CF0 means
The signal voltage of the electronics coolant temperature sensor drops close to zero, which almost always means the signal wire touches ground or the sensor is shorted internally. Low refers to the voltage, not to the temperature. GM sets the code below 2 % of the 5 V reference (0.1 V) in the 2011 Volt, the ELR and the 2016 HPC2 table, and below 4 % (0.2 V) in the 2016 Volt and the 2019 HPC2 table. Counting is 16 of 20 samples at 250 ms or 4 s in a 5 s window, with more than 9 or 10.2 V supply, Type B, two trips. The open or high case is P0CF1, a plausible but wrong value is P0CEF. With no usable reading, the controller assumes the worst, runs the pump and can limit inverter and charging power.
P0CF0 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0CF0
- Malfunction indicator lamp or hybrid warning
- Scan tool shows an implausibly high coolant temperature
- Pump running constantly, power or charging reduced
Common causes of P0CF0
- Most likelySensor signal wire shorted to ground
- PossibleInternally shorted temperature sensor
- PossibleWater in the connector bridging signal and ground
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hybrid electronics coolant temp sensor aWiring harnessHybrid control module
What each part of P0CF0 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. |
| F0 | The exact fault in that area. |
What to do next
- Note P0CF0 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 P0CF0
What does P0CF0 mean?
P0CF0 means "Hybrid/EV Electronics Coolant Temperature Sensor A Circuit Low". The signal voltage of the electronics coolant temperature sensor drops close to zero, which almost always means the signal wire touches ground or the sensor is shorted internally. It is a generic code, so it means the same on every make.
Is it safe to drive with P0CF0?
Drive gently and only to a workshop. With P0CF0 the car can go into limp mode (reduced power) to protect itself.
Will P0CF0 fail an emissions test?
Yes, it can. P0CF0 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 P0CF0 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. This is a job for a workshop.
Will P0CF0 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.