P0BB6Hybrid/EV Battery Voltage Sense Y 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
- The battery controller logs P0BB6 when the Y channel climbs above a level no healthy cell reaches. GM's first Volt of 2011 put that limit at 4.8 V or more, 1.4 s within 2 s, with the MIL after one trip. The 16OBDG02 programme samples every 100 ms and fails above 4.90 V in 14 of 18 samples, Type A; the eAssist battery fails above 4.65 V in seven of ten samples at 200 ms, Type B. A wiring fault that connects the Y input to the potential of the next cell is the most common explanation, followed by a failed input. Overcharging of a single cell is possible after a balancing problem and must be ruled out before the pack is charged again.
- What you may notice
- MIL and charging stopped
- Regeneration disabled
- Likely causes
- LikelySense input Y bridged to the next cell potential
- PossibleDefective input Y on the monitoring board
- RareOvercharged cell Y after a balancing problem
- 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.