P0BB6 code meaning
Hybrid/EV Battery Voltage Sense Y Circuit High
Powertrain system Generic code P0Bxx codes Check engine light
What P0BB6 means
The battery controller logs P0BB6 when the Y channel climbs above a level no healthy cell reaches. GM's first Volt of 2011 put that limit at 4.8 V or more, 1.4 s within 2 s, with the MIL after one trip. The 16OBDG02 programme samples every 100 ms and fails above 4.90 V in 14 of 18 samples, Type A; the eAssist battery fails above 4.65 V in seven of ten samples at 200 ms, Type B. A wiring fault that connects the Y input to the potential of the next cell is the most common explanation, followed by a failed input. Overcharging of a single cell is possible after a balancing problem and must be ruled out before the pack is charged again.
P0BB6 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 8 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0BB6
- MIL and charging stopped
- Regeneration disabled
Common causes of P0BB6
- Most likelySense input Y bridged to the next cell potential
- PossibleDefective input Y on the monitoring board
- Less likelyOvercharged cell Y after a balancing problem
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 yWiring harnessBms
What each part of P0BB6 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. |
| B6 | The exact fault in that area. |
What to do next
- Note P0BB6 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 P0BB6
What does P0BB6 mean?
P0BB6 means "Hybrid/EV Battery Voltage Sense Y Circuit High". The battery controller logs P0BB6 when the Y channel climbs above a level no healthy cell reaches. It is a generic code, so it means the same on every make.
Is it safe to drive with P0BB6?
Drive gently and only to a workshop. With P0BB6 the car can go into limp mode (reduced power) to protect itself.
Will P0BB6 fail an emissions test?
Yes, it can. P0BB6 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 P0BB6 to fix?
Difficulty: workshop only. A typical repair takes 1 to 8 hours of work. This is a job for a workshop.
Will P0BB6 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.