P0BAFHybrid/EV Battery Voltage Sense X Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0BAF covers a sense X signal that is electrically present yet does not behave like a real cell. For model year 2016 GM documents two versions in the same booklet. The Volt controller fails it when X moves in a different direction from the pack average, or by less than 0.005 V while that average moves more than 0.022 V, for 7 s within 8 s, Type A. The ELR variant samples every 200 ms, needs average movement above 0.006 V and fails after 20 of 40 samples, one trip. The eAssist hybrid asks for at least half of the average change, Type B over two trips, and GM's 2019 processor uses a 0.005 V trend test. Since the check pauses during circuit, low or high faults, P0BAF points to a stuck measurement rather than a broken wire.
- What you may notice
- MIL without obvious driving change
- Reduced electric range in some cases
- Likely causes
- LikelySense X value stuck while the pack voltage changes
- PossibleCalibration of the battery controller requiring reprogramming
- RareCell X with deviating internal resistance
- 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.