P0B71Hybrid/EV Battery Voltage Sense K Circuit Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0B71 belongs to the unsteady fault type: the channel K reading flickers or drops out momentarily without staying beyond a fixed limit. No manufacturer documents this code publicly. Neither GM's hybrid tables from 2011 to 2019 nor the Ford and Chrysler bulletins on cell sense codes mention it, although they cover the open, plausibility, low and high codes of neighbouring channels. Its basis is the CARB requirement to monitor battery voltage sensors of the energy storage system as input components. In a workshop the approach would be a wiggle test on the module harness while watching cell voltage K live, plus a check of the connector terminals for fretting corrosion.
- What you may notice
- Warning that comes and goes
- Occasional short loss of electric power
- Likely causes
- LikelyFretting corrosion on channel K connector terminals
- PossibleSense harness under strain losing contact with movement
- 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: €80 – €5,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.