P25C5 Brake Booster Temperature Sensor A Circuit Range/Performance

P25C5 is the plausibility fault for brake booster temperature sensor A: the circuit is electrically intact, but the reported temperature does not fit, for example a value that jumps implausibly, stays frozen while the motor works hard, or disagrees with the second sensor. No manufacturer documents P25C5 publicly. GM takes a different route on the 2023 Corvette Z06: rather than a separate rationality code, table 23OBDG07 adds up the signal voltages of temperature sensors 1 and 2 and logs the motor code C0582 as Type A once the sum exceeds 3.4 V for 0.6 s. That shows how two sensors can be checked against each other. A drifting sensor is the real hazard here, because the over-temperature protection of the electric motor relies on it.

Likely causes

Symptoms

• Brake warning message, sometimes only after long braking
• Brake assistance reduced as a precaution

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: gsi.ext.gm.com, bosch-mobility.com.