My ABS and brake light stated coming on 3 weeks ago. I read up on all the possibilties that would cause this problem which was speed sensor in the differental, so I replaced it but the ABS and brake light still came on and I had no cruise control either. I replaced the pump and module over the left fender with no success. A friend of mine said his buddy who runs a small shop for auto repairs just got a new Snapon scanner that read everything on a car or truck and he was intrested in helping me trouble shoot the ABS problem wanting to check his scanner out also. The scanner read 3 codes which I probably set off when replacing the pump and bleeding the brake system. After the codes were cleared I test drove the truck and same thing happened. He then scanned the ABS system again and it said BRAKE LIGHT SWITCH CLOSED. We pressed the brakes and the brake lights were working just fine. Then we inspected the wires going to brake light switch and everything was in order. We then decided to replace the switch any way. Upon removal of the switch there was a 6 wire plug to the switch. After removing the switch the plunger was stiff and barely moved as if the sping was boken internally. We replaced the switch and cleared the code again and now my ABS light problem has gone. Who would have ever thought a brake light switch would have caused this problem ?

 

thats probably my problem hahah

 

I've had that problem also, tried the speed sensor=no luck. Did you find an aftermarket brake switch? Thanks

 

Yep, I got it from Autozone, it was a stock item.......but I would think the code would have to be removed after installation.

 

My Speedometer was off by 6% because I had installed larger tires. I had read that if the rear end sensor speed did not match the tranny speed sensor reading it could set off the ABS light also, so while the mechanic had his scanner hooked up erasing the ABS fault code he changed my tire size so everything is now in sync. I don't actually know if the rear end and tranny sensors not being in sync will cause the ABS system to throw a code is true but it does make sense. I also thought this could only be done by a dealer but the mechanics new scanner was able to do the task.

 

It takes a special scanner that can connect to the ABS module. WIsh my Snap On MTG 2500 would do it but it does not. What scanner did he use?

 

I know it was a Snap-on SOLUS Ultra Scan Tool . Here is a link to it on Youtube;

 

Solis replaced the MTG series. Big bucks......My MTG may do it with the correct cables, but I have not gone through the assorment of cables and adapters to see.