P0BBBHybrid/EV Battery Voltage Sense Z 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
- If the Z channel shows a cell voltage above the upper limit, the controller sets P0BBB. The 2016 Volt battery module uses 4.8 V or more for 1.4 s in a 2 s window, Type A, and checks first that the cell monitoring slave is communicating and no open sense line is reported. The 16OBDG02 programme fails above 4.90 V in 14 of 18 samples, and the eAssist mild hybrid fails above 4.65 V in seven of ten samples with a healthy 12 V supply, Type B over two trips. Lithium-ion cells are not meant to exceed these values, so the reading normally points to a short towards the higher neighbour, a faulty input or a corrupted measurement, and only rarely to a truly overcharged cell. Charging is stopped as a precaution.
- What you may notice
- MIL and charging stopped
- Reduced regeneration
- Likely causes
- LikelySense lead Z shorted towards the higher neighbour cell
- PossibleFaulty measuring input Z
- RareCell Z overcharged
- 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: €100 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.