Tone Wheel and Wheel Speed Sensors: Overview

INSPECTION

Inspect tonewheel for broken teeth, this can cause erratic sensor signals.

Tonewheel should show no evidence of contact with the wheel speed sensor. If contact was made, determine cause and correct.

Excessive runout of the tonewheel can cause erratic wheel speed sensor. Replace assembly if runout exceeds approximately 0.25 mm (0.010 inch).