ABS LIGHT ON AGAIN OFF AGAIN

[ff emt-p bleve]

International ABS System on our new 2000 have been a on again off again problem with numberous trips to the dealer.Sensors seem very prone to wear/dirt/.Anyone else having problems with Internationals ABS system.

[capt 49-4]

We have a 2001 KME on an International chasis. We had problems with ABS light coming on took it to the dealer, they removed a switch that put the light out but guess what? Thank God we checked the truck out, It wouldnt pump. A factory man came out and fixed that and all was well. He ended up replacing a switch. I don't know which one as I was not there but it seems to work fine now?

<br />Stay Safe <img src="confused.gif" border="0">

[firmech]

Your in luck. I have been through the same scenerio that you are going through. I took 8 new trucks back and forth to the dealership numerous times for the same problem. The abs light comes on when there is a fault seen by the ABS computer. When the ABS light is on the antilock brake system becomes inactive so making the proper repair is very important to preserve the safety of your firefighters. The ABS system on your International is made by Bendix. The problem is the system is not wired correctly for a midship fire pump type vehicle. When you put your pump in gear your ABS computer detects vehicle speed via your speedometer. When it starts checking wheel speeds it checks the left front wheel sensor first. When the pump is in gear the wheels are not turning. The ABS system goes in to inactive mode and turns the ABS light on. The Bendix system does not reset itself and the light will stay on until it is cleared by a technician with a scan tool. If your dealership will call ED with International Service he can fax a drawing of the proper wiring. If I can help call me at the Tulsa Fire Dept. Garage at 918 596 1246 ask for John or email me at jhorton@ci.tulsa.ok.us

[medic1085]

Yea!! We have the same problem with a 1999 International 4900 had recall work done on the ABS system now the light is on continously, dealer having trouble figuring it out. <img src="mad.gif" border="0">

[firmech]

The problem was created when the recall was done. I really don't understand why International is not informing the dealers about this really important safety issue. When the light is on that part of the ABS is inoperative. Stopping distance is increased and vehicle control during skids is diminished. It is federal law to have ABS systems on trucks now.

The problem is correctable and is only on fire trucks with midship pumps and rail units designed to run on railroad tracks.

The repair basicly turns off the abs computer when the pump is put in gear. The abs computer will not see speedometer speed and thus will not detect a fault.

International has a drawing of the correct wiring. I have it at the shop and also the contact name and number with them.

[Resq14]

[quote]Originally posted by firmech:<br /><strong>Stopping distance is increased and vehicle control during skids is diminished.</strong><hr></blockquote>

<br />Correct me if I'm wrong, but isn't it true ABS does not decrease stopping distance? I thought it only improved the ability to steer under "lock-up" situations.

[RJE]

firmech - Bro - We're neighbors!

A. Ridge - you're correct - sort of. If the driver is "perfect" then ABS has no effect on stopping distance. What happens in reality, though, is one of two things.

Case 1, driver is afraid of over-braking, locking wheels, and then entering a skid, where steering is greatly diminished to impossible, and braking force is greatly reduced. So, they under brake, resulting in greater than optimal stopping distances.

Case 2, driver over-brakes, locks wheels, and enters that skid.

Case 1 w/ABS, no change.

Case 2 w/ABS, ABS prevents wheel lock (by un-applying the brakes) for short periods of time. This "slightly" reduces the amount of actual braking force applied (versus the "perfect" driver) but prevents entering that skid, so the real applied braking force is just under the maximum possible for the conditions.

In tests, race car drivers driving identical cars w/ and w/o ABS have been able to "beat" ABS stopping distances by slim margins. In the same tests, teenagers who'd just gotten their licenses stopped w/in 5% (some significantly less than that) of the "pros" using ABS, but went totally out of control without it.

[asaffell]

We are having trouble with our ABS light coming on right now. Unk cause as of this post.

[firmech]

OK I have the information in hand. I can fax it if needed. My suggestion is that you take your truck to the International Dealer. This is a warranty item because the problem was created when the recall was done. The ABS ECU was replaced and was not wired correctly.

Tell your dealer to call Mr. Edward F. Coleman of International Factory Service and Technical Support. His phone number is (219) 461-1896. Tell him you need the information on the "Bendix ABS /Split Shaft and Rail Truck Issue Fix".

I should have clarified myself on the stopping distance issue. Stopping is greatly decreased by ABS on heavy trucks when road conditions are slick. Slick being loose gravel, sand, water, ice and snow.

The following is an excerpt from the INSURANCE INSTITUTE FOR HIGHWAY SAFEY

<br />. Are antilocks required on big truck rigs? In March 1995, NHTSA issued a rule requiring antilock brakes for heavy trucks, tractors, trailers, and buses. All new truck tractors were required to have antilocks after March 1, 1997, and they were mandatory on new air-braked trailers and single-unit trucks and buses after March 1, 1998. And new single-unit trucks and buses with hydraulic brakes must have antilocks after March 1, 1999. This isn't the first antilock standard for U.S. trucks. A federal brake standard took effect in 1975, but its antilock and stopping distance requirements were suspended after litigation in 1978. Antilock brake systems have been required on all new trucks, buses, and trailers in Japan and the European Union for several years.<br />Antilocks are important for big trucks because they have poor braking capabilities compared with passenger cars. On dry surfaces, they take much farther to stop -- 47 percent farther in Institute tests. On wet and slippery roads, the stopping distance disparity is even worse. Tractor-trailer combinations also have the potential for loss of control and jackknifing on both dry and, especially, slippery roads. (Jackknifing occurs when the rear wheels of a tractor lock up, allowing the tractor to skid and spin so that it folds into the trailer. This can happen too when trailer wheels lock and cause the trailer to swing around the tractor.) Antilock brakes not only reduce stopping distances on wet and slippery roads but also help drivers maintain control.<br />The standard for tractors requires antilock control on the front axle and at least one rear axle. On at least one of the tractor axles, each wheel must be independently controlled by an antilock modulator. This ensures that a wheel provides shorter stopping distances and optimal braking force on all surfaces, especially on road surfaces where one side is slipperier than the other. For semi-trailers, at least one axle must have antilocks. Full trailers must have antilocks for at least one front and one rear axle.

[Rescue101]

Just for clarification;If the ABS light is on,you don't have partial ABS, you have NO ABS.The light is a warning that the ABS SYSTEM IS DISABLED.Your dealer may have to invest in a Vantage meter or scope,this is the only way speed sensors and other components can be accurately checked.ABS is just computer controlled braking,it isn't rocket science and repairing the system just requires checking inputs to the computer and outputs from same,then replace the defective component. <img src="wink.gif" border="0"> T.C.

[live_wire09]

Same here, we have a 1995 rescue that likes to do that from time to time, it really hasn't acted up till about a year ago. Oh, and how about some of those door sensors? You know what I'm talking about, get in the cab for a run, that lovely red light in the cab is flashing. You get out, run around the truck and check everything (looks like a chinese fire drill in the station) all is well, but that damn light keeps blinking because it isn't making contact with a compartment door some where. Oh, that's really great at night too. Talk about annoying.