P0C94: Sensor K's low circuit voltage converts to a hot value

P0C94 is hybrid/EV battery temperature sensor K circuit low. The 2018 GM monitor uses an NTC thermistor and a pull-up resistor. As the sensor signal voltage falls, the calculated temperature rises; a short to ground can therefore imitate a very hot sensor.

The reported quantity can be misleading

The table's failure criterion is calculated temperature above 160 °C. Eight of ten samples must fail, with each sample 100 milliseconds apart. The test requires system voltage above 10.2 V and excludes the specified battery-interface communication faults. Its reporting category is Type B, two trips.

This is a circuit-endpoint criterion. It does not prove that the battery physically reached that temperature, and it must not be presented as an acceptable thermal limit. Equally, the code alone cannot justify dismissing accompanying thermal warnings as a sensor error.

Establish credible temperature evidence

A technician should preserve K's value, related circuit codes and the other thermal measurements. Those observations guide the applicable procedure for separating actual heating from the electrical response described here. Replacing a cooling component solely from the displayed extreme would skip that distinction.

Verify an appropriate signal and completed monitor after repair. The exact sensor K location and test points depend on the vehicle. Work inside the battery requires qualified high-voltage personnel; no pack-opening or direct probing method is supplied by this monitor explanation.

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 922.