DTC 27 Left Front Wheel Speed Sensor Continuity Fault: Notes

Toothed wheel generates a voltage pulse as it moves past sensor. EBCM uses these pulses to determine wheel speed. Amount of voltage generated in each pulse depends on wheel speed and air gap between sensor and toothed wheel.

EBCM uses wheel speed sensor signal to calculate vehicle reference speeds and individual speed, acceleration and slip values for each wheel. These values are used to determine when anti-lock control is needed.

27 will set if short to battery voltage or open exists in circuit No. 830 or 873 or if wheel speed sensor is malfunctioning. Testing occurs with ignition on and vehicle at rest.

1. Checks for short to battery voltage in either wheel sensor circuit wires.
2. Checks for open in wheel speed sensor circuit wires.
3. Checks wiring and connectors for intermittents.
4. Checks if resets during key-up. If resets, wheel bearing/speed sensor assembly may be causing .
5. Checks if sets during road test.
6. 25 will set with vehicle in motion. 27 will set with vehicle at rest. If 25 sets, go to 25 chart.
7. Replace wheel bearing/speed sensor assembly. If resets, EBCM is concluding fault is present when no fault is present.
8. Ensures is not due to electro-magnetic interference.