P0B8BHybrid/EV Battery Voltage Sense Q 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
- P0B8B marks an open circuit on voltage sense Q, the seventeenth channel. In GM's BAS Plus mild hybrid tables Q is the first channel whose open test is blocked by code P1B37 instead of P1B36, which suggests it sits in the next measuring group of the battery interface module; the criterion stays lines N and N-1 below 1.4 V with a change above 0.5 V in 200 ms, 7 of 10 samples, Type B. GM's 2019 battery controller uses 0.8 s in a 1.6 s window, the 2016 version 0.6 s, both Type A with the 1.3 V and 36 mV criteria. The 2011 Volt list includes P0B8B as well. The two-mode NiMH trucks have no circuit code for block 17. Ford does not list it. Typically the vehicle restricts or blocks electric operation until repaired.
- What you may notice
- MIL and service vehicle message
- Electric operation blocked or limited
- Fuel consumption rises on hybrids
- Likely causes
- LikelySense lead Q open between cell tap and module
- PossibleLoose or corroded connector at the second measuring group
- RareFault in the battery interface module
- 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 – €6,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.