Diagnostic article Generic OBD-II
P25C6: Brake-booster temperature low is an electrical channel-one finding
P25C6 detects a low booster temperature-sensor signal, using repeated voltage evidence rather than proving the booster is cold.
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Documented application
2025 GM 25OBDG07A Part 2 documented monitor only; its application-matrix filename join is unresolved. No model, engine or universal calibration applicability is inferred.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P25C6 concerns the first brake-booster temperature-sensor channel in the cited EBCM table. The monitor looks for signal voltage below 0.2 V and interprets that state as a short toward ground. A low circuit-voltage code does not establish that the physical booster temperature is low.
Repetition is part of the criterion
The table requires the low reading on five consecutive occasions with ignition on. It lists a 0.600-second interval, continuous checking and two-trip reporting. A lone low sample, especially without its repetition history, is therefore not the whole documented fault condition.
The second temperature channel has a different low threshold in the same table. Do not borrow its limit when assessing channel one simply because both signals measure temperature.
Verification boundaries
A useful service record preserves the channel identity, raw electrical value and whether the consecutive-failure condition returned. A converted temperature display can obscure the actual voltage classification. Diagnosis of the brake system requires the applicable service procedure; this summary does not identify an accessible terminal or prescribe probing a powered brake assembly. The DTC describes an electrical input failure and does not establish brake-system safety or identify a replacement component.
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.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
Brake Booster Temperature Sensor A Circuit Low
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT