P0BB8 code meaning
Hybrid/EV Battery Voltage Sense Z Circuit
Powertrain system Generic code P0Bxx codes Check engine light
What P0BB8 means
P0BB8 is the open-circuit code of channel Z, the twenty-sixth and last cell channel with a generic P0 code. GM packs with more channels continue with manufacturer codes, for example P1B28 for the circuit of AA in the 2019 tables. The 2019 battery energy control module sets P0BB8 through the same seven cases as its neighbours, with 1.3 V between adjacent cells, under 36 mV on an active balancing gate or excessive splice voltage, 0.8 s in 1.6 s, Type A. GM's eAssist uses the voltage of lines N and N-1 below 1.4 V together with a change above 0.5 V in 200 ms, seven of ten samples, Type B and gated by P1B38. The 2011 Volt already listed P0BB8 among its open sense line faults.
P0BB8 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 10 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0BB8
- MIL and stop or service warning for the drive system
- Ready mode may be refused
- No charging
Common causes of P0BB8
- Most likelySense lead Z interrupted
- PossibleExcessive resistance at the splice or busbar of Z
- Less likelyMonitoring electronics input Z defective
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery voltage sense zWiring harnessBms
What each part of P0BB8 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. |
| B8 | The exact fault in that area. |
What to do next
- Note P0BB8 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 P0BB8
What does P0BB8 mean?
P0BB8 means "Hybrid/EV Battery Voltage Sense Z Circuit". P0BB8 is the open-circuit code of channel Z, the twenty-sixth and last cell channel with a generic P0 code. It is a generic code, so it means the same on every make.
Is it safe to drive with P0BB8?
Drive gently and only to a workshop. With P0BB8 the car can go into limp mode (reduced power) to protect itself.
Will P0BB8 fail an emissions test?
Yes, it can. P0BB8 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 P0BB8 to fix?
Difficulty: workshop only. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P0BB8 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.