P2E71Hybrid/EV Battery Pack B Cell Thickness Sensor Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2E71 flags the thickness sensor circuit of pack B as reading too high. Not every swelling detector is analog: LG's module patent uses a panel that slides along a ramp until it touches a contact sensor, and a Lithium Energy and Power patent fits cells with insulated contact elements that close under pressure. Ford also describes a thin wire across a weakened cell wall that tears once the wall bulges, cutting the current through it. In such switch-type layouts an open circuit and a triggered sensor can look alike, so the controller needs a defined resting level to tell them apart. No manufacturer documents P2E71 publicly. Check connectors after pack B service first; low signal is P2E72.
- What you may notice
- Hybrid or EV warning light
- Possibly limited power or charging
- Likely causes
- LikelySensor connector in pack B not fully seated after battery work
- PossibleBroken signal or ground wire to the sensor
- RareSignal line shorted to a supply voltage
- 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: €150 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.