The Chevy Cobalt has an anti-lock braking system (ABS) with sensors on each wheel that continuously monitor that wheel's speed. The ABS wheel sensor transmits this information to the ABS controller, which determines the amount of braking force to apply to that wheel during an emergency stop. The most common reason for replacing the ABS wheel sensor is metallic debris such as brake dust clogging the sensor.
Determine which ABS wheel sensor your Chevy Cobalt will need. You'll want to be sure the new wheel sensor is compatible with your make and model of Cobalt. All versions of the Cobalt have an ABS.
Disconnect the negative battery cable with a socket wrench and raise the vehicle. Unplug the electrical connector for the wheel speed sensor and remove the retaining bolt with a socket wrench.
Remove the front wheel speed sensor. You may need to remove the brake rotor with a socket wrench and use a blunt punch to push the sensor from the back side of the knuckle if it will not slide out of the knuckle.
Insert a socket wrench through the hole in the rear wheel hub flange and hold the retaining nut on the back of the hub with a wrench. Remove the retaining bolts and detach the rear wheel hub and bearing assembly from the vehicle. This assembly includes the rear wheel speed sensor.
Install the wheel speed sensors by reversing the removal procedure. Ensure the front wheel speed sensor lays flat against the bosses on the knuckle and use a torque wrench to tighten the retaining bolt to 107 inch pounds. Torque the retaining bolts on the rear wheel hubs to 37 inch pounds.
