Mercedes-Benz W211 E-Class ABS Brake Sensor Replacement

One of the most important safety developments have been anti-lock brake systems. In the system a sensor mounted in the hub measures the individual wheel speeds of all four wheels. Under braking if one wheel is traveling slower than the others the ABS Computer realizes the wheel is locking up. A locked up wheel no longer reacts to steering inputs and the car will slide until it stops. This reduces the ability of the driver to control the car. Here the ABS Computer can control the brake pressure to the locked up wheel. If the wheel is locked up the ABS computer can reduce brake pressure to that wheel. As the wheel speed sensor indicates the wheel is traveling at the same speed as the others the ABS computer allows pressurized brake fluid to the caliper to continue to slow down the wheels. This process alternates back and forth until the wheel speeds are under control. This allows the driver to come to a safe controlled stop. In this tech article we will go over all the steps to replace the ABS wheel speed sensor.

In order to replace the wheel speed sensor you will need to jack up and support your vehicle see our tech article on jacking up and supporting your vehicle.

The procedure for removing the front wheel speed sensor is the same on the left side as on the right side. In these photographs we are illustrating the right side being removed. Follow the same procedure on the left hand side to change that sensor.

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https://www.pelicanparts.com/techarticles/Mercedes-W211/06-BRAKES-ABS_Brake_Sensor_Removal/06-BRAKES-ABS_Brake_Sensor_Removal.htm

Time: 1 hour
Tab: $150
Tools: E10 Torx socket, 18mm wrench or socket with ratchet
Applicable Models: Mercedes-Benz W203 (2001-07)
Parts Required: ABS wheel speed sensor
Hot Tip: Twist ABS sensor first before attempting to pull out
Performance Gain: Repair needless ABS activation at low speeds