Here is a link I hope you find helpful:

http://www.aa1car.com/library/abs_kelseyhayes.htm

 

Yea, i've got the same issue going on. Accept I blew a wheel cylinder out, ever since then it's been throwing an abs/brake light. I've bled them and no change. Brake feel fine though, was hoping it was just the sensor on the rear diff, planned on changing that out next week.

 

HeyYou, what are you getting at here??? Are you thinking that the combimation valve might be stuck to only let fluid flow to the front brakes???? I did a few quick stops the other day and I was unable to get the rear brakes to lock up. However, it did feel like the rear brakes weren't working too well. If I can't find a scan tool, I might try your suggestion. Thanks.

 

I had a brake line blow out and both lights came on.Fixed the line and we bled them and got all the big bubbles out and the damn thing still wasnt happy.So we continued to bleed to get out every little bubble we could.We let it sit for little.Then bled it a little more.Bubbles were gone and the lights went out.Maybe you have a little air left in there.

 

That is exactly what I am thinking.

Good point. If the pedal feels spongy at all, this is a real possibility.

Need to be sure the rears are adjusted up properly as well.... though if you weren't in there at all, that probably isn't an issue.