P0B9BHybrid/EV Battery Voltage Sense T 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
- On the 2012 two-mode trucks sense T is block 20, the last of their twenty nickel-metal hydride blocks, and P0B9B shows how GM handles the missing neighbour: block 20 alone is multiplied by twenty and compared with the pack voltage, and a gap above 70 V in 160 of 170 samples sets the code as Type B. All other channels there use a pair of blocks. On lithium-ion packs the code means that cell T does not follow the pack average: the 2019 hybrid processor demands 0.005 V of movement when the average shifts by more than 0.022 V (35 of 40 samples, Type A), the 2016 Volt the same with a 7 s in 8 s window, and eAssist half the average movement in 20 of 40 samples, Type B.
- What you may notice
- MIL, drivability usually unchanged
- Hybrid assist or EV range slightly reduced
- Likely causes
- LikelyChannel T measurement stuck or sluggish
- PossibleBlock 20 voltage diverging from pack voltage on two-mode NiMH packs
- RareFaulty pack voltage reference used for the comparison
- 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.