C0059high severityChassis
ABS Isolation Valve Solenoid Circuit
on 2013 Audi S5 3.0L Supercharged V6 · AWD
What this code means
Malfunction in the ABS isolation valve solenoid, used to isolate the master cylinder from the ABS modulator.
Symptoms
- ABS light on
- Brake pedal feels unusual
- ABS not functioning
- Pedal sinks during ABS activation
Common causes
- Isolation valve solenoid failure
- ABS module internal fault
- Wiring open or short
- Contaminated brake fluid
Diagnostic steps
- Test solenoid resistance through connector
- Command isolation valve with scan tool
- Check brake fluid condition
- Inspect module connector pins
Repair notes
Replace ABS modulator assembly. Bleed brake system thoroughly.
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