Step by step guide on how to replace an
ABS wheel speed sensor
, depending on design the sensor can be made separately
or it could be integrated into the
wheel bearing assembly
Tools and Supplies Needed
- Replacement Wheel Speed Sensor
- Tool set
- Shop towels
- Protective eye wear
- Work gloves
Before you begin make sure to park the car on level ground with the emergency
brake on. If the vehicle needs to be raised do so safely with jack stands rated
to hold the weight of your vehicle.
- After the lifting the vehicle loosen and
remove the lug nuts and remove the tire.
Step 2 - Once the tire has been removed, locate
remove the brake caliper mounting bolts
Step 3 - After the bolts have been remove, grasp
the caliper and rock it back and forth slightly to loosen to remove, then place
it in a secure spot do not allow the caliper to hang by the brake hose.
Removing the Caliper Mounting Bolts
Step 4 - Remove both brake pads and place in a
clean area, never allow grease to connect the pad surface.
Remove Brake Caliper
Step 5 - Loosen and remove the brake caliper bracket
mounting bolts and remove the bracket.
Remove Brake Pads
Step 6 - Once the caliper mounting bracket has
been removed use a hammer to shock (if needed) the rotor loose to remove.
Remove Brake Caliper Mounting Bolts
Step 7 - After the rotor has been removed, it will
expose the ABS wheel speed sensor, on some models the sensor is simply bolted to
the rear of the spindle
Remove Brake Rotor
in which case the removal of the brake assembly is not needed.
Step 8 - Use a socket or wrench to remove the sensor
ABS Wheel Sensor
Step 9 - After the mounting bolt has been removed,
grasp the sensor to remove it from the
Removing Wheel Sensor Mounting Bolt
Step 10 - Locate the sensor wiring connector which
is usually near the frame or
ABS Wheel Speed Sensor Removed
Step 11 - Release the safety clasp and gently remove
the connector from the harness. Match the new sensor to the old unit to ensure proper
installing and operation.
Once the sensor has been replaced, the ABS warning light will go out without
resetting or clearing the codes in most cases. Some systems might require a ABS
scan tool to reset the system, but this not typical.
ABS Wheel Sensor Wiring Connector
The ABS brake system
Remove Wiring Connector
on wheel speed sensors and a electronic controller and pump activate the system.
These sensors are located on all four wheels to monitor the rotation speed of each
wheel. This monitoring is performed to help the
main ABS controller
brake system pressure to each wheel while the braking system is applied.
By doing this the wheel that is rotating a lesser amount than the remaining wheels
will experience a brake fluid drop in pressure to allow the wheel to rotate at the
same rate as the remaining wheels.
These sensors are prone to failures and will usually illuminate the red or yellow
brake system warning light
To determine if a wheel speed sensor has failed there is one of two methods that
can be used.
The first and most straight forward process is to attach an ABS system scan tool
to retrieve the trouble codes, once the code is discovered finding the code definition
is next which will tell you the sensor that has failed.
If no scanner is available an alternative method can be used. Remove the electrical
connector from each wheel sensor,
using a multi-meter
test the voltage produced while rotating the wheel, if no voltage is produced the
sensor has failed.
- Inspect the sensor stator ring to confirm there is no damage existing
to the ring. If the ring shows signs or damage replacement is required.
- Confirm the electrical connector is clean from dirt.
If further assistance is needed, our certified car repair technicians are ready
to answer car repair questions for free
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Article first published 2016-02-05