C0146high severityChassis
Brake Assist Solenoid Circuit
on 2021 Audi A4 2.0L I4 TFSI · AWD
What this code means
Malfunction in the brake assist solenoid that provides additional brake pressure during emergency stops.
Symptoms
- Brake assist inactive
- Warning light for brake assist
- Longer stopping distance in emergencies
Common causes
- Faulty brake assist solenoid
- Solenoid wiring open or shorted
- Module driver failure
- Solenoid mechanically stuck
Diagnostic steps
- Test solenoid resistance
- Check wiring to solenoid
- Command solenoid with scan tool
- Inspect for mechanical binding
- Test module output signal
Repair notes
Replace brake assist solenoid or repair wiring.
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