Wheel Speed Sensor: Testing and Inspection

Early Production ABS Testing Procedures
Without ABS Test Equipment
Wheel Speed Sensor Test

The wheel speed sensors should be checked very carefully, as follows.

1. Check for opens in wheel speed sensor.
a. Disconnect sensor from wiring harness at connector.
b. Connect an ohmmeter to the leads of the sensor and check for continuity. This test should be repeated while moving the wiring lead of the sensor in order to find any intermittant opens.

2. Check the internal resistance of the wheel speed sensor. Sensor resistance specs can be found under SPECIFICATIONS.

3. Check wheel speed sensor signal output at connector.
a. Set a high impedance digital voltmeter to AC VOLTS position, and connect to wheel speed sensor connector.
b. With the voltmeter connected rotate the wheel at about one revolution per second and check the meter. A small A/C voltage should be generated as the toothed sensor ring is passed by the stationary sensor. If not, check wheel bearing play, adjust if necessary, and retest. If there is no output, replace wheel speed sensor.