P0CB6: Battery temperature sensor O produces erratic data

P0CB6 identifies intermittent/erratic battery temperature sensor O behavior. The documented 2018 GM test concentrates on how the signal changes within a short window. A single displayed temperature cannot fully represent that evidence.

How repeated excursions are recognized

The controller integrates the absolute changes over ten samples. The listed threshold is above 10, with four failing evaluations among five at 100-millisecond intervals. Positive and negative excursions both contribute, so a stable average does not guarantee a passing result.

For this test, system voltage must be above 10.2 V and the prescribed battery-interface communication fault group must be inactive. GM specifies Type B, two-trip reporting. An intermittent connection is one source-supported possibility, not a diagnosis of a particular connector or sensor.

Preserve the channel and its context

Record sensor O's trace, current versus historical fault status and communication conditions. Keep an intermittent pattern separate from a steady discrepancy or a circuit endpoint; those observations may lead to different checks in the service procedure.

The O designation must be mapped using the correct vehicle documentation before any physical work. Repair confirmation should establish stable credible input while the diagnostic is enabled, not just a plausible value after a reset. The monitoring table provides no instructions for direct testing inside a high-voltage battery. Qualified personnel must use the manufacturer's access, isolation and repair procedures.

Source and applicability

This explanation follows the documented GM monitor, not a verified application to every vehicle with this code. Confirm the vehicle, reporting module and calibration in current service information. GM diagnostic table, physical page 940.