Brake Pulsing

[fire8033]

New to this site, so hello all My daughter came home from college today and while riding with her I noticed the brakes pulsing when she attempts to slow down. I did some research and some checking and found out that if I take the fuse out of the ABS system so it's disabled and all the pulsing stops. My question is, what part of the ABS could be causing this, any idea how to test it, possible cost, and how hard is it to change???

Thanks for any and all help

 

[Layinhp]

sounds like a warped rotor



problem shouldnt go away if you pull a fuse though

 

[fire8033]

No it's a pulsing/grabbing like the ABS system is trying to activate and when I pull the fuse and kill the power to the ABS System it completely goes away.

 

[jrford]

sounds like you might have a bad ABS sensor. . .
When the rear ABS sensor would start to go there was no light on the dash but the ABS would kick in at odd times. Eventually the ABS came on and stayed untill a restart. I was able to pull codes to find out what sensor it was. In this case it was the Rear.

 

[BlackedOutEXPO99]

i had the same problem it was my abs sensor which is unfortunatly in the wheel hub assembly the sensor is the expensive part not the wheel bearing but it is sold as a wheel bearing assembly so i would replace that. a good way to find out which wheel it is unplug the sensor wire it runs up the spindle up to the frame up front near the bumper unplug it and with the truck jacked up and a multimeter touch the two points inside the plug while having someone rotate the wheel measure resistance if the numbers are low or jump from high to low then it can be bad. it is very important to spin the wheel at a constant speed to get a good reading if the numbers get higher as you spin faster without dropping then the sensor is ok.

 

[LVmounty]

I would say warped rotors as well. Change them and see

 

[EasyRhino]

If it only does it with the ABS fuse installed, it is not warped rotors. Confirm this first. If so, then you will need to check the front wheel ABS sensors - they usually fial in the bearing assembly, which means that requires replacement - they are not replacable by themselves. FWIW, I would check that the ABS wiring harness is intact before replacing the bearing assembly. There is a connector junction just inside the inner fender well in the engine compartment. - who knows, maybe it's loose.