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Abs


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06-12-03, 11:52 PM   #1  
Abs

I have a 93 Ford Explorer and the ABS light on the lower right hand side of the steering wheel stay on during the whole time i am driving so what is ABS and what can i do so it want come on no more are is it suppose to stay on when i am driving please help me about to go crazy

 
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06-13-03, 03:25 AM   #2  
It could be one of Ford's 'Better Ideas". Check the manual, maybe it's supposed to stay on. My Z71 has a dash light which says the passenger air bag is OFF - go figure.

What is ABS?
It's probably the greatest invention since the wheel ------------
Anti-Lock Braking System.

When you have an emergency STOP situation your vehicle isn't going to turn sideways and spin half way around. It's a computerized pulsating braking system which keeps the vehicle going in a straight line. It will, if you're capable. allow to sometimes steer away from a possible accident if there is enough time and distance. And they even work on very wet highways.

I tested my first ABS vehicle the first week I owned it. A 1994 Cutlass Supreme. Pouring rain on a nice straight stretch of country highway. I hit the brakes fairly hard and 'Voila' the vehicle stayed in my lane. I went one better - got it up to 60 and really got on the brakes hard! Worked like a charm. I AM impressed!!!

The only drawback is to allow extra space between vehicles for braking. I beleive most owners manuals make this recommendation. Check your manual.

fred

 
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06-13-03, 07:21 AM   #3  
Joe_F
If the ABS light is on when you are driving, the ABS system is storing a fault code/there is a problem with the ABS.

Professional service required. Brakes are not something to gamble with unless you have the tools, knowledge, and service information to handle. ABS brakes complicates this issue.

 
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06-13-03, 11:17 AM   #4  
IN OTHER WORDS........... Get it somewhere fast and get the light checked out. If the ABS light is on its never good. It means the ABS system may not function properly when called upon.
Get it checked out SOON!!!
Billy

 
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06-13-03, 02:56 PM   #5  
fewalt an ABS equipped vehicle stops much faster than non ABS,if it didn't wouldn't be much of a safety device would it?

 
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06-13-03, 03:12 PM   #6  
Davo,

I don't believe you are right.
Four wheels that lock stopped are gonna stop quicker than an intermittant system!

But I do believe they are much safer in rain and snow conditions.
Maybe someone else has input????

fred

 
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06-13-03, 03:30 PM   #7  
When you understand how ABS works let me know,I've had alot of ABS training and word one is ABS stops vehicles faster and under control,explain how pressure hold,pressure decrease and pressure increase functions to me and how they relate to ABS function.BTW a skidding tire has lost traction to keep it in laymans terms.

 
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06-13-03, 03:40 PM   #8  
Sure, but a system that stops brake pressure isn't stopping is it?

 
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06-13-03, 04:03 PM   #9  
It most certainly does and in a big way.It ABS prevents wheel slip due to impending lockup and it does so wonderfully but at a big expense ABS brake pressure modulator valves are BIG bucks but they do the job required.You also have very sophisticated electronics and sensors non of them cheap.Think of Commander Data from Star Trek stopping your car doing all the calculations for you,my freind you stop quick and in control.All this happens pressure hold,pressure release and pressure increase faster than you blink.But I'm not here to educate this way I'm just trying to help people save a couple bucks.If you fenwalt want more info contact me by pm.Maybe I'll oblige but my time is limited,JoeF needs help lol

 
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06-13-03, 04:09 PM   #10  
Davo,

I don't believe we need to PM or instant message, this is an open Forum.

There appears to be two schools of thought on this subject.
It also appears that the old experienced guy can still be smarter than the certified techie.
In over 2000 posts I'll admit to being wrong - TWICE.

http://www.mucda.mb.ca/aboutabs.htm

http://www.abs-education.org/faqs/faqindex.htm

http://www.silhouet.com/abs.html

http://www.safety-council.org/quiz/absa.htm

http://autos.msn.com/advice/standard...=9201&src=News

regards,
fred

 
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06-13-03, 04:16 PM   #11  
The offer of pm was a polite way to stop the discussion.

 
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06-13-03, 05:54 PM   #12  
To both of you guys. ABS is not to stop an impending slip, because it cant detect impending. What it can detect is the difference in wheel speed from one wheel to the next via sensors. That is how ABS interprets slippage. ABS operates to regulate the pressure going to each wheel when a slippage is detected. It is definately a safer way to stop, because it will regulate and command the vehicle to stop in a straight line, as far as stopping faster...... NO, absolutely not. That is why your owners manual will tell you that when you have ABS brakes you should allow a greater following distance. If you are on smooth. dry, unobstructed roads then you might stop faster, because the ABS system is most likely not going to detect a slippage. But where are you going to find roads like that? Not where I live thats for sure.
Not trying to start a debate here, but both of you are correct in your own perspective.
Billy

 
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06-14-03, 06:10 AM   #13  
Joe_F
Bottom line:

Anything that comes between your tires and the road is going to impede traction be it ice, snow, water, dirt, gum . That is why even if you had 8 wheel drive on ice, you're not going anywhere .

ABS gives some folks a false sense of security. It doesn't replace driver interaction or skill.

Fred: A skidding tire is LOST traction, and this has been proven scientifically. That is why with old cars they would tell you to pump the brakes as opposed to locking them up.

 
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06-14-03, 01:22 PM   #14  
Joe,

I'm not really talking about traction!
I simply stated what each link above has claimed or provren.
ABS braking is not going to stop a vehicle quicker than standard brakes Period.
Even if a standard brake system locks all four wheels, it may have lose traction, but friction has taken over, and the vehicle will stop quicker than a computerized system that is intermittant
.
I love ABS brakes and swear by them. Because I know in an emergency situation the vehicle holds it's steered direction, and will not spin/slige sideways.
BTW, no one pumps brakes when they are on the damn cell phone, look up., and traffic ahead is stopped. The old system will lock up. And either asystem is headed for a rear-ender if your following too close or not paying attention.
And, I know all about pumping brakes on slippery road surfaces, I grew up in the snowbelt of NE Ohio.

My only gripe is that someone told me I was wrong, and that ABS will stop a vehicle quicker. That is not true!!!
ABS is undoubtably safer because you can brake and steer. But it requires MORE braking distance.

finis

 
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06-15-03, 05:45 AM   #15  
Joe_F
Fred:

Follow me .

You NEED to be talking about traction when you talk brakes, because the two are "related" in some fashion. Once again, ANYTHING between your tires and that pavement WILL cause loss of traction. That is why when you hydroplane, you can sort of "feel" the car "float", because, essentially, there is a film of water between your tires and the road.

If I'm driving my Trans Am and a ball rolls out into the street and I stand on the pedal to lock 'em up, and the wheels skid, I have lost traction. As you know, ABS prevents that by modulating the brake pedal/preventing lock up. If you drive different cars like I do (I own six, only one has ABS), you need to know the difference .

In simple terms, if the brakes lock, you've lost traction. That is what ABS is trying to avoid.

ABS is "safer" if applied correctly, just like anything else. A crappy driver in a 1974 Chevrolet or a crappy driver in a 2003 Chevy with ABS is still a crappy driver and no safety equipment will help that person, or perhaps prevent an accident.

Also remember then when you lock up the brakes, the car tends to spin when you skid. This causes:

1) The driver to panic, because now they feel like they are going to slide into something;
2) It throws your orientation off because you are going sideways and focusing on what to avoid;
3) Your thinking shifts from what to avoid to "what can I hit to do the least possible harm".

All that within a few seconds at most! .

My point is again, brakes and traction belong in the same discussion and ABS seeks to stop lockup of the brakes which is essentially loss of traction.

 
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06-15-03, 04:32 PM   #16  
Hi agian Joe,

I am totally with you. I undersatand traction, 'planing' skidding, spinning and all that.
And like I've mentioned a number of times, I do love my ABS.

But one fact remains, even with the loss of traction, at least on dry pavement, friction with locked-up non abs is still stopping the vehicle. Skidding friction is still braking.

It is still my belief that two almost identical vehicles, one standard, and one abs, that the standard brake vehicle will stop faster than the abs equipped.

Q - and don't even know. Does NASCAR(the safest vehicles made) run with abs??

fred

 
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06-15-03, 04:54 PM   #17  
Joe_F
Fred:

Anytime you are skidding, you're losing traction. Period. If you've ever seen the look on a cat's face when he/she is sliding across ice, that's a good example. No matter how much they try, they are slipping Poor kitty. LOL.

I believe that the ABS will stop it "faster" in the sense that it will pulse the brakes on and off fast enough to 1) prevent lockup and 2) slow down/dampen the vehicle to bring it to a halt.

Preventing lockup is the key to not losing traction and that is the key to stopping.

I'm sure there have been studies done by this on the car makers sides

I believe why owner's manuals state to give more distance with an ABS car is because a) Car makers need to "CYA", b) Carmakers don't want to give false confidence (see "a"), c) people have been trained by driver's ed among other things to "pump the brakes" to prevent lockup. In that perspective they have to be "retrained" .

The overall experience of ABS, as you said is "better", but the driver experience is the key here.

Not much into car racing, never was. Only like what I can drive on the street .

 
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06-15-03, 05:10 PM   #18  
Joe,

Have you read the five links I posted above?

fred

 
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06-15-03, 06:44 PM   #19  
Fred,

I did and I am with you Bud.
Billy

 
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06-15-03, 07:09 PM   #20  
Joe_F
I'm with Davo on this one

 
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06-15-03, 09:16 PM   #21  
Well,
Thanks for the replies. It now appears we need more RESEARCH!!

It's out to the Links early in the A.M. tomo. Maybe I'll get lucky and shoot another 78 like Saturday.

Monday evening it will be back to this Pesonal Confuser and more proof positive, if such exists.

take care all,
fred

PS - well, maybe golf tomorrow - it's pouring rain at 12:25AM - geez, I'm so surprised. Haven't been able to ATV across the creek since Feb!!!!!!!!!!!!!!!

 
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06-16-03, 05:33 AM   #22  
Joe_F
Have to ask yourself, if there was no added benefit why they would go through the trouble to add ABS.

I know with regard to brake design in ' 79, when Pontiac came out with the 4 wheel disc brake design on the Trans Am and Formula, shorter stopping distances were claimed and shown by magazines. I might have some OEM literature that shows something like that as well.

Point? Why implement something if there is no benefit? Only adds to the cost .

 
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06-16-03, 03:57 PM   #23  
Joe,
there certainly is a benefit, it's been mentioned above. That being able to safely steer to avoid an accident while braking at the same time.

But, more research on the subject now shows that most insurance companies QUIT giving discounts for ABS equipped brakes. The main reason being - some people aren't too brite.

fred

 
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06-16-03, 04:37 PM   #24  
Joe_F
Correct. ABS doesn't replace driver skill. A bad driver is a bad driver in a 1974 Chevy or a 2004 Chevy as I said prior .

 
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06-19-03, 10:42 PM   #25  
I am back in college to finish up my engineering degree so this stuff is fresh on my mind. School is also the reason I have not been around here in automotive for awhile. A car is stopped by friction of the air, the pull of gravity and road causing drag/friction. Out of all of those factors road drag and friction play a leading role in stopping a car in a breaking situation. To under stand friction you have to be aware of the two basic types for friction, static and kinetic. When tire contact patch has static friction (the wheel is not skidding) it has much greater friction then when its friction is kinetic (wheel skidding). In both static and kinetic friction the other to variables (air and gravity) are the same if the cars tested are of the same shape and weight. The formula for friction is:

F=µN

Where {f} is total friction and {µ} is the coefficient of friction and N is normal force.


A table of friction coefficients:


µ Static

Aluminum on Steel 0.61
Car Tire on Asphalt 0.90
Glass on Glass 0.94
Greased Metal on Metal 0.10



µ kinetic

Aluminum on Steel 0.47
Car Tire on Asphalt 0.72
Glass on Glass 0.40
Greased Metal on Metal 0.06




Physics are not a good ideas they are the law. You should also be able to find lots of Labs to demonstrate this for you if you need the physical reinforcement. All of the above can be proven mathematically. If you are really interested you can do a search on static friction and kinetic friction and find the formulas that are used to arrive the numbers in the table above, and the proof set for the formula. But it will at the very least require Calculus II level math. The formula I did include is basic algebra and should not be to complicated for any on the board to do. For the normal force value {N} in the forumla use the approximate weight applied to each tire on each tire. And in case you could not make heads or tails from the above I am saying that ABS WILL STOP YOU FASTER AND IN A SHOTER DISTIANCE. You can see in the table above when the surface is slicker the more of a difference in the static vs. kinetic coefficient. This explains why you see a greater benefit on slick surfaces.

 
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06-20-03, 04:32 AM   #26  
WeldGod,
I certainly wish you good luck and success in completing your engineering schooling.
All of what you have stated is great, and in theory may be true.
Maybe you'll do a comprehensive study, like so many others, and have more convincing results re ABS braking systems.

Here's something I found from gatech.edu:

" “What about braking performance?”

You may have noticed that the graph in figure one for adhesion coefficient vs. slip in ABS looks odd (undulating) when analyzing ABS effect on a gravel surface. This is caused from the wheel plowing into the gravel and slowing down then rolling again increasing the time it takes to stop. These is because the rotating tire will stay on top of this low traction road surface covering, and effectively “float" on this boundary layer. A non-ABS braked vehicle can lock its tires and create a snowplow effect in front of the tires which helps slow the vehicle. These locked tires can often find more traction below this boundary layer. This is the case in road surfaces such as slush and snow as well as gravel.

When braking on dry or wet roads your stopping distance will be about the same as with conventional brakes."

According to this, both your statement and mine re ABS stopping distances may be incorrect.
Thus, at this point, I'm willing to compromise on this discussion. But we all agree, when ABS is used properly, braking and being able to steer for crash avoidance is a certain benefit.

study hard,
fred

 
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06-20-03, 02:00 PM   #27  
Baldguy
As to the original post

The ABS system on 1st generation Exploders has been an occasional sore point with some of us owners. I have not yet had a problem with mine, but have heard of other owners having problems with some actually removing the fuse for the ABS with improved braking. I'm not advocating this, just stating what some have done.

There is a great website devoted to owners of Exploders and you may be interested in reading what some owners have to say about their Fords. I do believe there is recent discussions in the forum relative to the ABS light remaining on with the system still functioning as it should. Here's the link and I've found it helpful.

http://www.explorerforum.com/forums/index.php

 
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