P0C8F code meaning
Hybrid/EV Battery Temperature Sensor J Circuit Low
Powertrain system Generic code P0Cxx codes Check engine light
What P0C8F means
P0C8F means the voltage on sensor J has dropped below its valid window. The NTC thermistor is powered via a pull-up resistor, so a grounded signal line reads as an absurdly hot cell group; low refers to the signal. GM's HPC2 table of 2019 (19OBDG02) converts the voltage and fails the test if the result is over 160 °C for 8 samples out of 10, sampled every 100 ms and rated Type B. The older 2012 Volt table judges all sensors together and fails them above 87.5 °C (raw count under 680) for 1.4 s of a 2 s window. On the 2018 Outlander PHEV, Mitsubishi logs a short of sensor [09] once the signal remains below 0.12 V, hotter than 125 °C, for 2 s. A genuinely overheating pack would instead set P0A7E. Expect reduced power and battery cooling running hard.
P0C8F at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0C8F
- Warning lamp with clearly reduced electric power
- Battery fan or chiller running constantly
- Engine starts more often on plug-in hybrids
Common causes of P0C8F
- Most likelySensor J signal wire chafed and shorted to ground
- PossibleThermistor J shorted internally, for example after moisture
- Less likelyMonitoring board input pulling the line low
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery temp sensor jWiring harnessBms
What each part of P0C8F 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. |
| 8F | The exact fault in that area. |
What to do next
- Note P0C8F 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 P0C8F
What does P0C8F mean?
P0C8F means "Hybrid/EV Battery Temperature Sensor J Circuit Low". P0C8F means the voltage on sensor J has dropped below its valid window. It is a generic code, so it means the same on every make.
Is it safe to drive with P0C8F?
Drive gently and only to a workshop. With P0C8F the car can go into limp mode (reduced power) to protect itself.
Will P0C8F fail an emissions test?
Yes, it can. P0C8F 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 P0C8F to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0C8F clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.