Shut Down for ABS Light?

Ziggy,You stated your tractor doesn't have an ABS malfunction warning light.If your running a tractor older than March of 1997 then your tractor wasn't required to have ABS or the warning light.Trailers were to have an integrated system with a warning light by 1998 but was put off until 2001 because of technical problems.So if you have a tractor manufactured after March of 1997 you have an ABS system and a dash malfunction light.If the system is working fine you'll only see the light come on at start and at shutdown for a second.If you don't see the icon come on during this time the bulb may be blown.A mechanic I know showed me how to recycle the ABS module usually located over the rear axles to get the light to go out.He said it is not always a sensor malfunction just a software issue.As he called it"That stupid black box with the blinking lights".

 

Let me rephrase...when I said "I don't get a ABS light for the tractor" I meant that it doesnt come on. I have an 06 Century. I have the various lights and gizmos...etc, and the tractor light did come on for a short period of time but I think that was just a sensor that was dirty or something...can't remember. However, the trailer ABS light on the instrument panel on the dash comes on every now and then. Sometimes its on all day, sometimes its off and on....sometimes never. I dont know if that is a sensor somewhere or what the deal is. My thing is that...how does the tractor know there is a issue with the ABS on the trailer? The only thing that connects the tractor and trailer are the air lines and electrical lines (outside of the kingpin)...so how does the tractor know there is an ABS issue?

 

This was a big issue prior to the law taking effect that mandated a dash board malfunction indicator light.The trailer manufacturers had to come up with a way to power the trailer ABS without disrupting other electrical accessories or functions on the trailer.This is why you did not see this rulemaking take effect in 1998 but rather 2001.Your trailers ABS system ECU is powered by your tractor to trailer power cord through the number 7 pin(should be blue).This is also where your tractor recieves info on the status of trailer ABS operation.Manufacturers do for the most part use a system called PLC4TRUCKS but with some variations with more benefits.Also their coming out with better wheel sensors that are not subject to moisture and dirt and distance from the tone ring.This will help solve false indicator light ups.Also in the news,the CVSA is fighting the NHTSA over a rule that would abolish external ABS indicator lights on trailers after March of 2009.Will see what happens.