P0CB2 code meaning
Hybrid/EV Battery Temperature Sensor O Circuit
Powertrain system Generic code P0Cxx codes Check engine light
What P0CB2 means
P0CB2 is the catch-all electrical code for battery temperature sensor O, reserved for circuit faults that are not classified as low, high or erratic. Publicly, no manufacturer documents this exact code. Counting the rationality list in GM's 2011 Volt table puts O in position 15 of 16, but GM only uses P0CB3 to P0CB6 for it. Mitsubishi maps O to module sensor [14] of the Outlander PHEV and likewise relies on the rationality, short and open codes alone. CARB section (e)(15.2.3)(A)(iv) counts battery temperature sensors among the inputs that have to be monitored, and (A)(v) asks for codes that point to the smallest replaceable unit. With O unusable, the controller has to guess the module temperature and normally cuts battery power. The thermistor sits inside the pack, so repair is a high-voltage job.
P0CB2 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 P0CB2
- Hybrid or EV system warning, possibly with check-engine lamp
- Reduced electric power or charging rate
Common causes of P0CB2
- Most likelyPoor contact at the sensor O connector on the monitoring board
- PossibleDamaged lead between thermistor O and the board
- Less likelyFaulty measuring channel in the cell monitoring unit
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 oWiring harnessBms
What each part of P0CB2 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. |
| B2 | The exact fault in that area. |
What to do next
- Note P0CB2 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 P0CB2
What does P0CB2 mean?
P0CB2 means "Hybrid/EV Battery Temperature Sensor O Circuit". P0CB2 is the catch-all electrical code for battery temperature sensor O, reserved for circuit faults that are not classified as low, high or erratic. It is a generic code, so it means the same on every make.
Is it safe to drive with P0CB2?
Drive gently and only to a workshop. With P0CB2 the car can go into limp mode (reduced power) to protect itself.
Will P0CB2 fail an emissions test?
Yes, it can. P0CB2 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 P0CB2 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0CB2 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.