CAR House

the traction control and abs warning light on my 95 840 light up and stay on until i turn the engine off. sometimes they do it and sometimes they don't.
bmw told me it could cost thousands to find the cause.

I have the same problem on my 840 -95
Any ideas how to solve this?

Have you replaced both batteries with fresh new ones? More often than not, E31 electrical gremlins come out when the batteries are on their way out.

I also have the same problem on my 95 840. Whats happening!

Brand new batteries checked all connections but still the same

Are the wheel sizes within the 2% tolerance perimeters for E31? The ASC system is very sensitive.

yes

tmc, broraxelson

Did you find out what the problem was?

Check the following:

Is there a "grinding/gurgling" noise coming from the ASC+T Hydro Unit? (it is located under the brake booster)
Are any of the hose to or from the PENTOSIN container leaking/weeping fluid?
Have you cleaned/changed the PENTOSIN Container filter as well as the ASC+T filter (located at the base of the engine between engine and radiator)?My ASC Light came on intermittantly last year and it was due to a faulty Controller (driver's side door sill). Got that reprogrammed and everything went well for almost a year and now I have ASC+T Hydro Unit failure (waiting on a unit from Jim in New York). I also am replacing the 2 high pressure hoses and the 2 low pressure hoses in this system (all had varying stages of dry rot - not surprised after 200,000 miles). Both filters are also being replaced.

Hope that gives you some insight.

Cheers GR8White

No grinding/gurgling.
Did find a hose weeping today, the one from the PENTOSIN canister to bottom of pump and will order a replacment and a PENTOSIN canister filter tomorrow.
Definatly cant find the ASC+T filter between the base of radiator and bottom of engine, did the 840 definatly have one?

Have also tryed the holding brake pedal and ASC+T Switch and turning on ignition to get fault codes but the light just stayes on.

I went over as much of the wiring today as I possably could, removed and replaced all relays and fuses in turn and disconected and reconected as meny conectors and cleaned everything and earth points. Was just hoping it would cure something.

Regards Luke.

slightly different setup from the 850 (sorry didn't see you had a '40) No ASC+T filter up front for you. Make certain you get the correct PENTOSIN canister filter, if I remember correctly, there are 2 different types - one is a type of paper filter, while the other is a sintered brass filter (much like the old carburator fuel filters in older American cars). You could possibly be sucking in air through that old hose....

If it won't self test you need to check the connections to the controller in the drivers door sill (LHD)

I would guess that the connections are corroded from when someone steam cleaned the carpets.

steam cleaning is somewhat of a myth. Have you ever taken one of these carpets out of the car. They are very THICK and padding is somewhat waterresistant. I would imagine if you spilled a large 48 oz cup of liquid directly over the module, you might have some trouble, but the modules themselves are also fairly water resistant. Now, if the car was submerged to the point that the carpet is under water all bets are off. In this case, the water would be coming in UNDER the carpet and directly into the module. I have steam cleaned a carpet from one of the parts cars several times trying to get the stains out, and the underside remained dry...

If it won't self test you need to check the connections to the controller in the drivers door sill (LHD)

I would guess that the connections are corroded from when someone steam cleaned the carpets.

I pulled up all the trim and carpet and removed the module about two weeks ago, everything was dry and clean and all connectors were good. I lightly tapped the module on the steering wheel a couple of times (sometimes works) and put everything back together but it made no differance.

Think its time to book it in at the dealer. Thanks again for all your help. Regards Luke.