P0B45Hybrid/EV Battery Voltage Sense C 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
- Voltage sense C is the third cell or cell-group measuring channel of the battery monitoring electronics, not a pack voltage input like P0ABA. P0B45 reports an electrical break in that channel. GM's battery energy control module sets it when its open sense line test fails for 0.6 s: adjacent cell readings at least 1.3 V apart, a cell below 36 mV while its balancing switch is on, or a splice above 0.1 V (bus bar splice 0.5 V); Type A, one trip. Ford lists P0B45 with the other open-line codes on the 2019-2020 Fusion plug-in hybrid, fixed by a new traction battery, and on the 2023 Mustang Mach-E and E-Transit, where an intermittent BECM flexible printed circuit is blamed. Expect no start or no charging.
- What you may notice
- Vehicle does not start or does not become ready to drive
- High-voltage battery no longer charges
- Powertrain warning (wrench) and Stop Safely Now message
- Likely causes
- LikelyOpen cell sense tap, splice or bus bar connection on channel C
- PossibleIntermittent flexible printed circuit between cells and battery controller (Ford Mach-E, E-Transit)
- PossibleInternal traction battery failure requiring pack replacement (Ford Fusion PHEV)
- 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 – €8,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.