P0B88Hybrid/EV Battery Voltage Sense P Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- 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.
- What you may notice
- MIL and reduced propulsion power
- Auto stop no longer active
- Likely causes
- LikelyLead P shorted to a lower potential or chassis
- PossibleDefective input in the battery interface module
- RareWeak cell or NiMH block 16
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.