My ! light on the dash and pad are on and the Antilock light is on.  Does this mean that I need new brake pads?  I know that there is some kind of sensor that reads the brake shoes or something.

Will
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It means that the ABS system is not functional , each wheel has a speed sensor ,there is a hydraulic unit in the left front fender which has two relays mounted on top under a plastic cover ,and the system has a "brain" control unit . Your braking ability is compromised when the unit is not operational .

Jim

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At 03:16 AM 11/14/00, Dan wrote:
Jim,
Is the ABS system necessary.  As I understand it, it is possible for the ABS to cause more problems than it solves.  Am I working under an urban myth?


My understanding is:
A really, really GOOD driver can stop faster without ABS on dry pavement.

Very, very few drivers can stop faster without ABS on wet pavement, snow, ice, etc.
 

No one can beat ABS on mixed surfaces (slick on one side).

Most drivers simply won't push the pedal hard enough to activate ABS on dry pavement, which means that most drivers don't use all of the available braking ability. Mercedes has added a feature to their top lines to help this. If you push the brakes hard, the car will actually apply more pressure, up to ABS limits. This can reduce panic stop distances quite a bit for the average driver.

In several years of 928 driving, I have gotten into ABS ONE TIME on dry pavement. I have gotten into ABS quite a few times on wet pavement.
Luckily, I don't get many chances to try ABS in ice or snow here in Atlanta.

Wally Plumley
928 Specialists

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Yes, I think Wally and others that replied are exactly correct.  In consistently low coefficient surfaces I find that I use the ABS more than I probably should.  I also find that drivers tend to  be right on the edge in bad weather, much closer to disaster than I think they realize.  I will be stopping with traffic in the snow/ice and the ABS starts working.  Other drivers seem to be oblivious.  I think it definitely pays for itself in wintertime fender-bender situations.  It's just not perfect.
I don't know if many notice, but a few seconds after you start the car the ABS goes through a self-test routine and if you are stepping on the brake at that time you might feel a little bump on the pedal.  That is the ABS getting its morning exercise.

Gary Casey

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I think this means everyone on the Renn list , right !  Wally wrote ... "Areally, really GOOD driver can stop faster without ABS on dry pavement."
....
Perhaps if you have practiced braking at the limit many , many times and know exactly what the road surface is like , only brake on the same spot , know how much weight is in the car. But real world 100 mph and a deer wanders out into your headlights after you had dinner and a couple glasses of wine , I think I would want the ABS . You get the nearly maximum braking yet retain the ability to steer around Bambi . Point being when you lock up the brakes the car no longer steers it just slides in the direction it was going , tires that are not rolling have zero directional control .

Jim Bailey

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I agree with Jim - it takes a very good driver that probably knows he is going to make a stop to beat the ABS, but on dry pavement is one place that ABS is typically not quite as good as the good driver.  In other cases even a good driver cannot beat the ABS.  Some ABS systems are better than others, though.  We found that the best advice to give "ordinary" drivers is that if they are panicked put both feet on the pedal and press as hard as you can.

Trying to think about steering, not locking the wheels when totally panicked out is not a good thing.  Better to just lock 'em up and spend the time anticipating the upcoming crash.  Do the same thing with an ABS, but then you can actually steer.
Incidentally, in a lot of cars (my 928's have been close) you run out of boost before the wheels lock on dry pavement - you have to push through the booster (exerting a lot more force) to get the wheels to lock.  I was a passenger in a minor accident (old SAAB).  Someone pulled out from a side street, the driver braked hard, I thought "we should be stopped by now"..bang.  I went back and looked - one rear wheel just barely locked and the two fronts didn't leave any marks at all.  He either just pushed until the booster ran out or pushed until he heard the squeal.  Either way we could have stopped in time if he had locked up the fronts.

Gary Casey