P0B72Hybrid/EV Battery Voltage Sense L 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
- P0B72 reports an open circuit on voltage sense L, the twelfth channel. One detail sets it apart from its neighbours: GM's 2011 hybrid tables list every open sense line code from P0B3B upward except P0B72 (and P0B90), so the early system did not use it, while L's range, low and high codes were present. Later GM tables include it. The BAS Plus mild hybrid sets it when lines N and N-1 fall below 1.4 V with a change above 0.5 V in 200 ms, 7 of 10 samples, Type B; the 2019 battery energy control module uses its adjacent-cell, balancing and splice tests within 0.6 s, Type A. Ford's Fusion plug-in hybrid bulletin for 2019-2020 includes P0B72 and replaces the traction battery.
- What you may notice
- No start or no ready mode
- Battery or hybrid system warning
- Charging aborted
- Likely causes
- LikelyOpen sense lead, crimp or cell tap on channel L
- PossibleInternal traction battery failure, pack replacement (Ford Fusion PHEV)
- RareHigh-resistance splice or bus bar joint
- 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.