P0B95: Sense S is an electrical-pattern diagnosis

P0B95 names voltage-sense channel S within the cited battery controller's open-line checks. The diagnosis concerns the integrity of a measurement path. It is different from estimating how much energy the battery can hold, even when both concerns appear in a workshop discussion.

What the controller is comparing

For a general sensing-line interruption, GM compares the affected reading with an adjacent cell reading and uses a difference greater than one volt. A separate common-power-line pattern uses a difference greater than half a volt. The comparison must persist over the documented 600-millisecond window.

The source also describes a power-loss case in which a slave measuring circuit is unpowered and all affected readings become zero. Consequently, the distribution of abnormal readings can be more informative than the lowest displayed number alone.

Preserve the enabling conditions

Sensing-module communication must be available, and specified balancing or internal-performance faults must not be active. The protection self-test must not be running. Those prerequisites explain why a technician should document companion faults before using an absent retest failure as confirmation.

The letter S is a controller channel designation, not a universal pack-access location. A qualified high-voltage specialist should identify the correct hardware mapping and service procedure. The table's incomplete busbar branch prevents reproducing a complete decision tree, but the supported adjacent-reading patterns remain useful evidence for that investigation.

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.