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Wheel Speed Sensor: Testing and Inspection

FRONT/REAR ABS WHEEL-SPEED SENSOR INSPECTION
Visual Inspection
1. Remove the wheel and tire, and inspect the sensor for looseness and damage. Replace the sensor if necessary.

Clearance Inspection





1. Inspect the clearance between the wheel-speed sensor and the sensor rotor.
Clearance 0.3 - 1.1 mm (0.012 - 0.043 inch)

Resistance Inspection
1. Disconnect the ABS wheel-speed sensor connector.
2. Inspect the resistance at the ABS wheel-speed sensor.
^ If not as specified, replace the ABS wheel-speed sensor.
Resistance 1.3 - 1.7 KOhm

Voltage Inspection
1. On level ground, jack up the vehicle and support it evenly on safety stands.
2. Disconnect the ABS wheel-speed sensor connector.
3. Inspect each sensor by rotating each wheel one revolution per second.
^ If not as specified, replace the ABS wheel-speed sensor.
Voltage 0.25 - 1.2 V (AC)

Voltage Pattern Inspection





1. On level ground, jack up the vehicle and support it evenly on safety stands.
2. Disconnect the ABS wheel-speed sensor connector.
3. Using an oscilloscope, inspect the voltage pattern for distortion and noise by rotating each wheel.
^ If there is distortion or noise. inspect the ABS sensor rotor.