P0BA4: Sense V and the limits of an open-circuit conclusion

GM lists P0BA4 as voltage-sense circuit V within a shared open-line diagnostic. The number identifies the reported channel, but the diagnostic evidence includes adjacent cells and common measuring-power paths. It does not by itself name a failed battery module.

Follow the type of disagreement

The general sensing-line branch compares neighboring readings and uses a difference greater than one volt. A separate common-power-line branch uses a half-volt difference. The table also notes that loss of an individual slave ASIC supply can produce zeros across all affected measurements. This makes a multi-channel pattern an essential part of interpreting an apparently isolated circuit code.

The open-line detection window is 600 milliseconds, evaluated at 200-millisecond intervals. Neither a single value nor a dashboard warning conveys that complete evaluation history.

Check the measuring system's availability

The controller requires enabled communication and excludes named sensing-module communication, balancing and internal-performance faults. The secondary protection self-test must be inactive. Those restrictions can explain why the code does not repeat during an unsuitable retest.

Record V and its surrounding readings for the high-voltage specialist, who must establish the correct pack and channel mapping from service information. Do not infer a connector location from the alphabetic label. The source contains an unfinished busbar comparison, so this article deliberately avoids presenting a complete electrical fault-isolation procedure or an invented missing limit.

Source and applicability

15OBDG01 Hybrid Diagnostics, cited controller and monitor only. Historical calibration limits are not universal specifications; per-code vehicle, engine and hardware applicability must be verified.

GM source, physical page 635 · GM source, physical page 636.