Ordinary scan tools for reading engine fault codes are usually no help when it comes to reading fault codes or doing other diagnostics on antilock brake systems
. It takes special software to access the ABS diagnostics, which usually means using a factory scan tool, a high end professional scan tool, a dedicated ABS tester, or a DIY scan tool with dual capabilities, but we can still check the basics.
Start with the brake fluid, if low, add some, and look for leak if low.
When a wheel speed sensor
(WSS) fails or there's a problem in the sensor's wiring circuit, it usually disables the ABS
system and causes the ABS warning light to come on. Loss of a wheel speed signal is a serious problem because the ABS module needs accurate input from all its sensors to determine whether or not a wheel is locking up. Without this vital information, the ABS system can't do its thing.
Check fuse 17(see diagram)
Visually check the speed sensor. Check for lose or disconnected wire at each senor, look for mud covering the air gap between the sensor and the tone ring. Each tire must be removed to access each sensor
sending the diagram to your email.
Thursday, January 7th, 2010 AT 10:26 AM