My ABS and Brake Lights are on. This Happened to me once before. When it did I noticed that my brake fluid was above the full line, so I took a soda straw and took fluid out until it was back to the full line. After that, my lights went out and everything was normal. Well, the lights have come back on again about two months later and the fuild in the master cylinder was above the full line again. I dropped the fluid level back down to what it should be, but the lights remained on this time. Any idea whats going on? BTW, the car in question is a 89 Bonneville SSE.

Well I read up alittle on the matter here on the boards, and learned alille bit on the matter. I went out and started the car after it had a chance to cool down, and now the lights are off! Anyone still have anything to say about this?

well there are notorious problems with the Bosch ABS systems in our generation. This is a new one to me, I have heard of losing fluid, but not gaining it! IS the fluid clean? Are you using the correct fluid? (DOT 3) I don't know how that would change things, but it might expand when hot?

Its funny you mention that about 2 weeks ago I had to syphon a 1/4 " or so out of MC but its been ok and never had any lights come on at all.But wonder why it was over the fill line all of a sudden.

the abs accumulator may be failing and loosing pressure, when the accumulator loses pressure or is depressurized the fluid from it goes into the resivoir.

with the ign on, how many pedal pumps does it take to get the abs and brake lights to come on? with the ign off how many does it take to get the pedal hard?

btw the accumulator is the cartoon like bomb looking thing on the master cylinder.

Dont want to hijack but it does seem like a pressure problem ,I had them bled at a shop cause they still were soft after I bled them and they still are abit soft,is the accumulator easy to change.I have a parts car.

chances the parts car one is worn out too, its as simple as screwing the accumulator off, u need a uh allen wrench if im right to get it off. make sure you dont destroy the oring tho. new ones can be had for 80 if i remember right. gm part number: 25528382

It would still be worth a shot if it is that easy to change, with the used one.