CARspec had the opportunity to diagnose and repair an unusual yet fairly common issue on a 2000 Lexus RX300. The owner was concerned that the antilock brakes (ABS) would operate during normal driving and braking. It was to the point where at every stop sign, light, or turn the ABS would activate. Understandably concerned about the safety of the vehicle the owner brought it to us to have it diagnosed.
After driving the vehicle and experiencing the ABS issue the technician inspected the brakes for wear or signs of malfunction – because the ABS relies on the friction brakes to work, make sure the entire friction brakes were up to specification was the first step. After confirming the brakes were ok, the technician inspected the rear axle ABS tone wheels. Frequently the tone wheels, made of high and low spots the ABS sensor reads to monitor the speed of the wheel, develop a crack. Instead of a consistent high-low-high-low notches the wheel now has one spot that reads high-low-low-high, the same signal an ABS system would see if the wheel had suddenly stopped. This causes ABS activation and the feeling the owner was concerned over. Here’s the cause:
Broken Tone Wheel
The repair is to rebuild the axle and replace the tone wheel. CARspec offers rebuilt Lexus genuine axles to reduce the overall price. As Eden Prairie and Chanhassen’s independent Toyota and Lexus repair shop we’re always happy to share the more interesting issues we see. If you’ve got odd ABS or brake issue, don’t hesitate to give us a call at (952)426-2798 today!
