P0A2C: Low motor-A sensor voltage appears as an extreme hot indication

For the cited motor A controller, P0A2C represents the low-voltage end of the motor-temperature sensor circuit. GM associates it with a reported temperature above 230°C and a signal near zero volts. “Low” therefore identifies the electrical side of the conversion, not the temperature direction.

The monitor is different from overtemperature protection

The row is enabled with wakeup on and uses 250 failing counts in a 350-count window, at approximately 10.4ms intervals. Its purpose is to identify a temperature signal outside the allowed electrical range.

P0A2F, on the same page, instead evaluates sustained motor overheating while the temperature signal is in range and the plausibility fault is absent. An extreme P0A2C indication should therefore not be used as unquestioned physical temperature evidence for the separate thermal monitor.

Retain the electrical interpretation

Record the exact motor A temperature parameter, its validity status and related sensor or reference faults. A display fixed at an extreme value may be a signal-limit result; the source does not establish whether a sensor, connection or controller input caused it.

The printed voltage is not a universal test point or permission to probe the inverter. Use the correct motor-controller circuit information and approved diagnostic access. A qualified high-voltage technician should perform any physical investigation after the prescribed isolation process, rather than treating a sensor code as a low-risk standalone wiring task.

Source and applicability

GM 2010 10OBDG10 Hybrid Diagnostics, only the cited controller and monitor. These are historical calibration examples; individual vehicle, engine and hardware applicability is not established. GM PDF, page 287.