C0145high severityChassis
Brake Assist System Malfunction
on 2002 Subaru Impreza 2.5L H4 · AWD
What this code means
The emergency brake assist system that provides additional braking force during panic stops has malfunctioned.
Symptoms
- Brake assist warning light
- Reduced braking force during emergency stops
- ABS light may also be on
Common causes
- Brake pedal position sensor fault
- Brake pressure sensor malfunction
- ABS module failure
- Brake booster assist solenoid fault
Diagnostic steps
- Test brake pedal position sensor operation
- Check brake pressure sensors
- Perform emergency stop test and observe brake assist activation
- Inspect brake booster assist solenoid if equipped
- Check for related pedal sensor codes
Repair notes
Diagnose root sensor or actuator fault. Brake assist uses data from multiple sensors.
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Other Chassis codes on this vehicle
C0021
LF Wheel Speed Sensor Range/Performance
C0022
RF Wheel Speed Sensor Range/Performance
C0023
LR Wheel Speed Sensor Range/Performance
C0024
RR Wheel Speed Sensor Range/Performance
C0025
LF Wheel Speed Sensor Circuit Intermittent
C0026
RF Wheel Speed Sensor Circuit Intermittent
C0027
LR Wheel Speed Sensor Circuit Intermittent
C0028
RR Wheel Speed Sensor Circuit Intermittent
C0035
Left Front Wheel Speed Sensor Circuit
C0036
Left Front Wheel Speed Signal Erratic