P0B7F: the block 14 high branch is a direct range check

GM's entry for P0B7F is block 14 voltage measurement out of range high. The standardized circuit N high label provides the broad category, while the table supplies the historical controller's precise range-check behavior.

Distinguish a high report from a comparison failure

Block 14 must read above 23 V. Fifteen failing observations among twenty samples, collected at 100 ms intervals, establish the documented failure. The condition does not require the neighboring block to be low or a block-to-pack calculation to exceed a threshold.

Those other tests exist in nearby rows, but they answer different diagnostic questions. If a workshop reports multiple block-related codes, keep each code's status and data instead of assuming all are proof of one failed battery component.

Evaluate the supply and operating state

RUN mode, a 9–18 V low-voltage supply and absence of active P0A1F are required. These prerequisites describe when the controller can judge the signal. They do not define a manual test voltage for the traction-battery sensing circuit.

Useful verification includes the block 14 reading during eligible operation and review of any returning companion faults. The source is a monitor summary, not a replacement instruction or a universal hybrid specification. The vehicle's detailed service procedure is needed to determine whether the high measurement is physically real, and high-voltage access requires qualified technicians.

Source and applicability

GM 2010 10OBDG10 Hybrid Diagnostics, cited BPCM or hybrid-controller monitor only. Historical calibration values are not universal specifications; no per-code model, engine or hardware fitment has been established. GM PDF, physical page 229.