Abs and Brake lights come on while driving.

[byerda]

Just got my module back from modulemasters, and it was the best $150 I have ever spent. ABS and brake light went out immediately and have not come back on! After trying to repair the bad gound as the first step in the problem, the dealer told me i needed a new module at $400 and then to install it would be more. Got the module off (not an easy thing to do, had to grind the bolts heads off of two of the bolts) sent it off and a week later got it back. Modulemasters gave me a 5 year warranty, great service that saved me tons of money!

[1999silverado1500z71]

byerda, was your problem similar to mine? For a while the lights came on every so often and you could turn them off by restarting the truck and then as time went on the lights come on almost everytime you drive it. What did you all have to do to get the module off? Did you have to take the pump off also? It doesnt look like there is much space to take the module off without taking the pump off.

[a.j.vaughan82]

would this cause like a pulsing feel on the pedal just before u stop, cause mine is doin that, i havent had it scanned yet but the abs light came on almost once a day for like two weeks then hasnt been back since but the pedal thing bugs me its like hitting a patch of ice just as u come to a complete stop thankfully i dont live in the city so not too many short stops. o i have a 2004 gmc sierra 5.3 4x4 crew 105k mi

 

 

This may be the low speed ABS activation that has plagued Chevy's and GM's. The ABS will activate while you are braking and get down to 5 mph or so. It has to do with corrosion building up under the Wheel Speed Sensors on the front wheel hubs, causing a bad signal to the ABS system.

 

There are a number of posts on this, but basically, after checking the front wheel speed sensors, you can remove, clean the mounting surface and re-install.

 

Thats what it was i was telling my dad about it and he said my moms Equinox did the same thing, told me not to get generic or parts store brand get oem sensors cause he had gotten the cheaper and they werent the right size. This will have to wait till next weekend ths weekend i got rained out thanks again guys

[asc08]

"Thats what it was i was telling my dad about it and he said my moms Equinox did the same thing, told me not to get generic or parts store brand get oem sensors cause he had gotten the cheaper and they werent the right size. This will have to wait till next weekend ths weekend i got rained out thanks again guys"

 

 

If the issue is the build up of corrosion on the sensor mounting location, there is no need to purchase anything, other than maybe some anti-seize to coat the surface with, after you clean it down to bare metal. For my '06, the sensors alone were more than the hub assembly with the sensors installed!

 

Remove the wheel, caliper and rotor.

Disconnect the electrical connector from the Wheel Speed Sensor (WSS)

Connect a digital voltmeter to the WSS wire

Spin the hub by hand.

If you get a reading of less than 350 millivolts AC (or .35 volts AC), you should clean the mounting surface.

Remove the one screw that holds the WSS in place, I believe it is an allen head, (don't remember the size)

Pull the WSS out (pull straight up)

Plug the hole with something to keep debris out. I used an ear plug.

Clean the surface to bare metal, I used a dremel tool, but you will need something more than a scraper or wire brush.

Coat the bare metal with anti seize, and replace the WSS.

Give it a spin with the volt meter attached. If you have 350 millivolts or more, you are good to go.

Repeat on the opposite side.

While you have the tools out, go around and check the grounds on the chassis, especially the one under the driver's door, and clean and re-attach as needed.

 

Good luck, it really is not a very difficult job.