Tone wheels can cause erratic wheel speed sensor signals. Inspect tone wheels for the following possible causes:
If a front tone wheel is found to need replacement, the halfshaft must be replaced. No attempt should be made to replace just the tone wheel.
If a rear tone wheel is found to need replacement, the rear hub and bearing must be replaced. No attempt should be made to replace just the tone wheel.
If wheel speed sensor to tone wheel contact is evident, determine the cause and correct it before replacing the wheel speed sensor or tone wheel.
Tone wheels are pressed onto their mounting surfaces and should not rotate independently from the mounting surface. Replace the front halfshaft or rear hub and bearing as necessary.
Check the gap between the speed sensor head and the tone wheel to ensure it is within specifications.
Excessive tone wheel run-out can cause erratic wheel speed sensor signals. If tone wheel run out is excessive, determine if it is caused by a defect in the halfshaft assembly or hub and bearing. Replace as necessary.
Wheel speed sensor to tone wheel air gap specifications:
Tone wheel run-out specifications: