C0025moderate severityChassis
LF Wheel Speed Sensor Circuit Intermittent
on 2009 Audi A6 3.0L Supercharged V6 · AWD
What this code means
The left front wheel speed sensor signal drops out intermittently during driving.
Symptoms
- ABS light on intermittently
- Sporadic traction control activation
- ABS works sometimes but not always
Common causes
- Damaged wiring at flex point near suspension
- Corroded connector pins
- Intermittent sensor internal fault
- Loose sensor mounting
Diagnostic steps
- Wiggle-test wiring harness while monitoring sensor signal
- Inspect connector for corrosion or backed-out pins
- Check sensor mounting bolt torque
- Road test while monitoring live data
- Inspect wiring routing near suspension components
Repair notes
Repair wiring at chafe point or replace connector. Re-secure sensor.
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
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
C0040
Right Front Wheel Speed Sensor Circuit