P0B68: sense-J diagnosis continues the shared open-line monitor

P0B68 is listed as battery voltage-sense circuit J in the cited GM BECM table. Its row appears on a continuation page, while the shared open-sensing criteria begin on the preceding page. Reading only the J row would miss the diagnostic mechanism.

The shared criteria are part of this code's evidence

The monitor uses relationships between affected and adjacent cell readings and separate busbar-related cases. It also describes a sensing-power loss that can drive multiple reported values to zero. These are measurement-path patterns, not direct proof of failed battery chemistry.

The continuation adds restrictions for communication, balancing and internal module status, plus a separate protection self-test. A J-channel result should therefore be reviewed with those supporting states.

Avoid a false sense of precision

The source does not provide a physical J-channel connector map. Its positive-side busbar comparison is also incomplete, so this draft does not claim a full numerical repair test from the summary alone.

Record J together with neighboring channels and the event's controller state. That provides the qualified technician with evidence to distinguish an isolated sensing issue from a shared supply or module problem.

After the actual defect is demonstrated and repaired, allow the appropriate monitor to evaluate with its prerequisites satisfied. A code that stays absent while supporting faults inhibit the monitor is not a completed pass. High-voltage access remains governed by the vehicle-specific isolation procedure.

Application limits

Document-level 2015 GM diagnostic table; per-code vehicle/engine/calibration applicability not established.

Source

15OBDG01 Hybrid Diagnostics, physical PDF pages 635, 636.