For 1990-2009 cars only
The wheel speed sensor produces an AC voltage whose amplitude and frequency vary, depending upon the velocity of the wheel. The ABS control module (EBTCM) uses this voltage signal to calculate wheel speed.
DTC Parameters
DTC will set if:
A wheel speed = 0 km/h (0 mph) and the other three wheel speeds are greater than 8 kph (5 mph) for 2.5 seconds and no wheel speed sensor circuit malfunction DTCs are set.
When DTC sets:
| • | The ABS telltale will be On. |
| • | The control module will disable ABS. |
Diagnostic Aids
The inline connectors at wheel speed sensors are the most likely area for opens and shorts.
When diagnosing intermittent conditions, use the Scan tool to observe parameters while testing driving or wiggling a wire harness. Compare parameters with those on a known good system.
Possible causes for DTC to set:
| • | Wheel speed sensor has low or not output. |
| • | Excessive air gap. |
| • | No speed ring. |
| • | Wheel speed sensor shorted. |
