P0B88 code meaning
Hybrid/EV Battery Voltage Sense P Circuit Low
Powertrain system Generic code P0Bxx codes Check engine light
What P0B88 means
A too-low value on sense P, the sixteenth channel, is what P0B88 records. GM's BAS Plus mild hybrid sets it at a cell sense line below 1.4 V for 7 of 10 samples, sampled every 200 ms and only with the 12 V battery above 8.8 V; it rates the fault Type B. The full lithium-ion systems in GM's 2016 and 2019 tables react at 0.2 V or less after 1.4 s in a 2 s window and set it as Type A. In the 2012 two-mode NiMH pack, P is block 16; blocks 16 and 17 must both stay below 2 V for 15 of 20 samples. A collapsed reading usually traces back to a short between the P lead and a lower potential, sometimes to a defective input; it is rarely the cell itself. The open-circuit condition is reported separately with P0B86.
P0B88 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 P0B88
- MIL and reduced propulsion power
- Auto stop no longer active
Common causes of P0B88
- Most likelyLead P shorted to a lower potential or chassis
- PossibleDefective input in the battery interface module
- Less likelyWeak cell or NiMH block 16
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 pWiring harnessBms
What each part of P0B88 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. |
| 88 | The exact fault in that area. |
What to do next
- Note P0B88 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 P0B88
What does P0B88 mean?
P0B88 means "Hybrid/EV Battery Voltage Sense P Circuit Low". A too-low value on sense P, the sixteenth channel, is what P0B88 records. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B88?
Drive gently and only to a workshop. With P0B88 the car can go into limp mode (reduced power) to protect itself.
Will P0B88 fail an emissions test?
Yes, it can. P0B88 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 P0B88 to fix?
Difficulty: workshop only. A typical repair takes 1 to 8 hours of work. This is a job for a workshop.
Will P0B88 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.