P0BC3 code meaning
Hybrid/EV Battery Temperature Sensor E Circuit Range/Performance
Powertrain system Generic code P0Bxx codes Check engine light
What P0BC3 means
P0BC3 is the plausibility check for battery temperature sensor E, GM's sensor 5: its reading is compared with the other pack sensors, which should agree closely. GM's 2016 hybrid table fails it when E is more than 25 °C away from the average of the others in 50 of 67 samples; the 2018 CT6 plug-in table more than 20 °C for 5 s within 6.7 s; the eAssist mild hybrid (13OBDG05C) allows only 8.55 °C, and only after the module has been off for more than six hours. All are Type B, two trips. The check is suspended while circuit codes are active, so it points to a sensor that reads wrongly but in range, or to a real hot spot. Volt bulletin 18-NA-342 counts it among codes that set falsely in cold weather and fixes them by reprogramming.
P0BC3 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0BC3
- MIL on after two trips
- Battery too cold or reduced power message
- Limited charge and discharge power
Common causes of P0BC3
- PossibleSensor E drifting or poorly seated on its cell group
- PossibleModule software setting the code falsely in the cold (GM Volt)
- Less likelyReal local hot spot from a weak cell group or blocked airflow
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 eWiring harnessBms
What each part of P0BC3 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B | Area: hybrid propulsion. |
| C3 | The exact fault in that area. |
What to do next
- Note P0BC3 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 P0BC3
What does P0BC3 mean?
P0BC3 means "Hybrid/EV Battery Temperature Sensor E Circuit Range/Performance". P0BC3 is the plausibility check for battery temperature sensor E, GM's sensor 5: its reading is compared with the other pack sensors, which should agree closely. It is a generic code, so it means the same on every make.
Is it safe to drive with P0BC3?
Drive gently and only to a workshop. With P0BC3 the car can go into limp mode (reduced power) to protect itself.
Will P0BC3 fail an emissions test?
Yes, it can. P0BC3 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 P0BC3 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will P0BC3 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.