ABS Warning Light Stays On

[omar]

My car has been in the garage for over a year now and it is about to be recomissioned - but the damn ABS light and brake warning lights stay on all the time. The accumulator gets hot and the unit it is attached to makes a noise. Does anyone know the cure to this problem?
The car is an American spec 1989 V12 auto convertible.
Thanks
Omar

[HerefordMark]

Omar, I did my car's brakes a while ago so might be able to help. The noise I suspect is the ABS unit trying to charge the accumulator. The noise should stop after a few seconds, so if it doesn't that might indicate a leak somewhere. I have heard that accumulators need replacing every few years. The other thing you could check is the level of fluid. If it's been standing for any time you ought really to change it, but in the meantime make sure the reservior is fully topped up. I had a real problem with mine in that the fluid was up to the mark, I had rebuilt the entire system, but both brake and ABS lights would not go out. Eventaully I solved it by adding a bit more fluid - evidently the system is very sensitive to levels.

HM

[omar]

Mark,
Tremendous response as far as I am concerned - thankyou very much.
I now know that I need to replace the accumulator (always a good thing anyway) and top up the fluid level to slightly above where it should be.
Many thanks again.
Omar

[poprivet]

The fluid reservoir has a front and back section with an internal wier, both parts need to be topped up to the MAX line.
The spheres can be re-charged providing that the internal diaphragm isn't perforated. I had mine done by Pleides at a much lower cost then a new one. Don't delay a repair as that pump motor will burn out fast if it is running far more then it was designed to, and having no brakes will seriously ruin your weekend.
Pop

[nigel1]

You can also get a new accumulator from the States (GM Part I think).
I got one a couple of years back, its exactly the same as the original from my 93 XJS. Cost about $100, but you need to get a proper quote on the shipping, it can vary tremendously depending on the supplier.
The GM part number is 25528382

[omar]

Chaps,
Thankyou very much for you tremendous responses.
I had no intention of driving the car in its current state, but the warning is much apprecaited. I will investigate the GM part number option as GM cars are a penny a dozen here. I think Range Rovers also use the same sphere. I know from my Rolls-Royce accumulators that these are lifed items. the diaphragm inside tears after time and that makes the sphere a useless bit of kit.
many thanks again.
Omar

[omar]

here is the latest.

I now know all there is to know about ruddy accumulators. The american GM part number is not recognised in Dubai but I am sure it is a common part in the states. Range Rovers have the same accumulator and are a third of the price in Dubai.

I split a failed accumulator to see what was inside and i now have a bullet proof test to assess the condition of an accumulator. All you have to do is insert a rod (with a flat end - not a sharp point) in the threaded hole of a removed accumulator to see if you can feel the diaphragm within the first 1 or 2 inches. if the rod hits a rubber wall then the accumulator is ok. if the rod apperas to go in further than 2 inches then the accumulator is scrap.

good luck.javascript:emoticon(':lol:')
Laughing

Omar

[omar]

Now I can tell you all that the accumulator was not the only source of the light staying on. I got an accumulator from a Range Rover (part number STC 2784) which was a fraction of the price of a Jaguar part. But the light did not go out!! the problem was the multi-pin switch near trhe accumulator. changing both accumulator and switch did the trick.