System: Powertrain (P-Code)
SAE Standard (Generic)
Family: Brake Booster Temp Sensor
Code P25C4: Brake Booster Temperature Sensor A Circuit
Diagnostic & Technical Explanation
Code P25C4 (Brake Booster Temperature Sensor A Circuit) sets when the ECM/brake module sees an open, shorted, implausible, or intermittent signal from the temperature sensor inside the electric or hydraulic brake booster, used to protect the booster motor from thermal overload during repeated hard stops. Causes are a corroded connector at the booster assembly, chafed wiring in the firewall harness, or a failed internal thermistor that requires booster-level service.
First-listed procedure
Rank #1
Clean booster temp sensor connector
Moderate DIY
This is the first procedure in the authored
consideration order, not a measured cause likelihood. Execute it only when its prerequisites
and diagnostic findings support it. Its cost and labor estimates (where known), the step-by-step procedure and the
remaining 2 procedure(s) are in the licensed dataset. Ordering context.
Full family: Brake Booster Temp Sensor
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)