What goes wrong
The wheel speed sensor monitors the rotational speed of each wheel and sends this data to the Anti-lock Brake System (ABS) control module. When a sensor fails, the ABS module loses critical input, interpreting this as an anomaly. This can lead to the disablement of the ABS, Vehicle Dynamics Control (VDC), and cruise control systems, as well as illuminating various warning lights on the dashboard.
Symptoms to watch for
- ABS warning light illuminated
- Traction Control warning light illuminated
- Cruise Control warning light flashing
- Vehicle Dynamics Control (VDC) warning light illuminated
- Check Engine Light (CEL) illuminated (less common)
- Loss of ABS functionality
- Erratic speedometer readings (rare)
Root cause
Often, the wheel speed sensor fails due to corrosion of the sensor body or the wiring harness, or due to physical damage from road debris. Internal electronic failures within the sensor itself are also common.
Permanent fix
- Replacement of the faulty wheel speed sensor and inspection of the wiring harness. Clearing of stored trouble codes.
- Using an OEM Subaru wheel speed sensor, part number 27540FJ000 (front) or 27540FG000 (rear), is recommended for optimal durability and compatibility.
FAQ
What causes wheel speed sensor failure?
Often, the wheel speed sensor fails due to corrosion of the sensor body or the wiring harness, or due to physical damage from road debris. Internal electronic failures within the sensor itself are also common.
How much does it cost to fix?
National average $250–$450.
Is this a DIY repair?
Difficulty 3/5. Replacement of the faulty wheel speed sensor and inspection of the wiring harness. Clearing of stored trouble codes.
What are the symptoms?
ABS warning light illuminated; Traction Control warning light illuminated; Cruise Control warning light flashing; Vehicle Dynamics Control (VDC) warning light illuminated; Check Engine Light (CEL) illuminated (less common); Loss of ABS functionality; Erratic speedometer readings (rare)