P25C7: A high booster temperature input does not prove overheating

The cited P25C7 monitor checks whether brake-booster temperature channel one exceeds 3.27 V. GM classifies the condition as a signal short toward supply. The word “high” applies to the electrical input; it should not be translated into a confirmed overheated brake booster.

What makes the result repeatable

Ignition must be on, and the source requires five consecutive occurrences of the high reading. The listed check interval is 0.600 seconds, with continuous operation and two-trip reporting. A momentary value without the recurrence pattern does not reproduce that complete criterion.

Channel two’s high limit is different in the same source. Using a neighboring sensor’s threshold can incorrectly change which readings appear abnormal, so establish the channel before interpreting voltage data.

Use the right evidence

Retain raw signal information and monitor status alongside any displayed temperature. A plausible converted temperature is not automatically a pass if the electrical input is intermittently rejected. Conversely, this DTC alone does not prove actual thermal stress. Any circuit access must follow the vehicle’s brake-system service information; the summary contains no safe universal probe point, component-isolation sequence or replacement recommendation.

Document scope and source

2025 GM 25OBDG07A Part 2 documented monitor only; its application-matrix filename join is unresolved. No model, engine or universal calibration applicability is inferred. These figures explain the cited controller logic, not a vehicle-specific repair instruction. Match the vehicle’s service information before applying them.

GM physical PDF page 77.