abs pulsates over 45mph on 2000 bonneville

Hi,,, this is puzzling...when braking over 45 mph you can feel the abs kick in and pulsate the petal but when the speed drops under 45 it stops and its smooth braking,,,any ideas?

Only a scan with an abs function will solve this, look at comparative wheel speed inputs for any anamolies.

I did an abs scan and the only code was a low tire pressure scan....does anyone know how many volts at what speed does the wheel hub sensors put out and how much variance there can be?

that dont sound like abs activation. it sounds like ur brake rotors are warpped and need to be machined.

thought the same thing and replaced the rotors and brakes ( which I planed to do anyways before the problem started) its weird because you can feel the abs kicking in...that grindy, pumping feeling you feel when that abs motor/pump works

pull the abs fuse and see if it does it with the fuse out then you will know for sure if its abs related, if it doesnt do it with fuse out it is in the abs, but the abs light will be on and it will throw a code because of it so dont chase that code

any idea what this could be?

Did you get a full abs scan as suggested???

It sounds to me like you have a bad wheel hub assembly, but testing this with a multimeter will not be a great thing....

You need to have it scanned while driving with either a Tech II or a Snap On.... This is going to be the only way you'll know whats wrong with the ABS system without throwing a ton of money at the car trying to correct it..