P0B90Hybrid/EV Battery Voltage Sense R Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0B90 is stored when the battery controller concludes that the tap of sense R, the eighteenth cell channel, is open or too resistive. GM's 2019 battery energy control module runs seven cases for it: neighbouring cells 1.3 V or more apart, a reading under 36 mV while the balancing gate is on, or splice voltages above 0.1 V (0.5 V at a busbar splice). The fault has to be present for 0.8 s within a 1.6 s window and is Type A. The 2016 Volt and ELR use the same cases with a 0.6 s window. Oddly, GM's first-generation Volt tables of 2011 to 2015 contain no P0B90 at all, although they list the circuit codes of S to V. Range, low and high faults of R are P0B91 to P0B93.
- What you may notice
- MIL with service hybrid or EV system warning
- Reduced propulsion power or no ready mode
- Charging interrupted or refused
- Likely causes
- LikelyLoose, corroded or broken tap of sense lead R
- PossibleExcessive resistance at a splice or busbar joint feeding channel R
- RareFaulty measuring or balancing input on the cell monitoring board
- 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: €150 – €7,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.