EDIT: Nevermind. upallnight got me confused with this old thread. I see that you had a bad DSC module and replaced it to solve this problem. Please add to the first post and change the title to include SOLVED.

I don't understand why you don't just follow the test plan in DIS? Why guess?

Anyways, I'm not all that familiar with that but I wouldn't think sensors are not connected to the valves per se. I'm thinking there's something wrong in a module/pump/wiring.

Did you have any recent work done to the DSC/ABS module or near that area? I thought I read that the fittings/wiring to DSC/ABS module can be damaged easily if not paying attention.