P0AB5Hybrid/EV Battery Pack Air Temperature Sensor B Circuit Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0AB5 is set when the signal of battery air temperature sensor B fluctuates in a way real air temperature cannot, typically from an intermittent contact. No manufacturer documents this exact code publicly; GM's two-mode tables, which use sensor B as the outlet air sensor, list only P0AB2 to P0AB4. As an analogy, GM's 2019 table judges the battery cell sensor code P0A9F by summing signal changes within 10-sample windows, failing after 4 of 5 bad windows, Type B. CARB requires hybrid temperature inputs to be checked for erratic behaviour. The fault often comes and goes with vibration or temperature. Move the outlet-side harness while watching live data to locate the weak point.
- What you may notice
- Hybrid warning light that appears intermittently
- Outlet air value jumps in live data
- No noticeable driving change in most cases
- Likely causes
- LikelyLoose or corroded terminal at sensor B
- PossiblePartly broken wire near the outlet duct
- RareInterference coupled into the sensor line
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.