Brake Booster Temperature Sensor A Circuit Intermittent/Erratic
The booster temperature signal jumps or drops out for short moments. Usually a loose connector or a chafed wire that opens during vibration or thermal expansion.
Affected components
- Electric brake booster
- Temperature sensor
- Wiring harness
Common causes
- High likelihood: Sensor connector not fully seated or pin tension lost
- Medium likelihood: Harness chafed against booster housing or pedal bracket
- Low likelihood: Connector with intermittent contact under vibration
Possible symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.