P0B9EHybrid/EV Battery Voltage Sense T 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
- P0B9E would describe a sense T signal that flickers. It lacks any public manufacturer documentation. Even the 2012 two-mode trucks, whose last NiMH block is channel T, monitor it only for range, low and high, and GM's lithium-ion controllers add a circuit test but no intermittent one. The requirement behind the whole code family comes from CARB 1968.2: battery voltage sensors of a hybrid energy storage system are monitored components, and manufacturers must store separate codes that lead to the smallest part replaceable in service. A technician facing this code would wiggle-test the channel T wiring while watching the cell voltage live and look for a reading that dips or spikes for a fraction of a second.
- What you may notice
- Intermittent warning lamp
- Occasional brief loss of electric drive
- Likely causes
- LikelyLoose or spread terminal in the channel T connector
- PossibleConnection that opens with temperature changes
- RareElectrical interference coupling into sense lead T
- 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.