Brake/ABS Light Illuminated

[jimnance]

I have a 1993 2500 CTD. It's has fairly fresh brakes. Both the brake and ABS lights just illuminated. Fluid levels are fine. Any ideas on where the problem may lie??



Thanks.

 

[MMeier]

I have a 1993 2500 CTD. It's has fairly fresh brakes. Both the brake and ABS lights just illuminated. Fluid levels are fine. Any ideas on where the problem may lie??



Thanks.

Speed sensor thingie in your rear diff, up top.

 

[1stgen4evr]

I was chating with MarkH about this the other day. He has traced ONE of the possible reasons to a fuse link in the computer behind the glove box. He is far more 'electrical' than I. You can find him in a post lower down regarding flexplate woes. Nice guy. You could PM him and I am sure he would give you the explanation.



I on the other hand can assure you that if you eliminate the system all together, you will have better brakes and no lights ever. Some describe this as slash and burn, that is fine. I got good brakes and no surprises.



James

 

[TWorline]

I was chating with MarkH about this the other day. He has traced ONE of the possible reasons to a fuse link in the computer behind the glove box. He is far more 'electrical' than I. You can find him in a post lower down regarding flexplate woes. Nice guy. You could PM him and I am sure he would give you the explanation.



I on the other hand can assure you that if you eliminate the system all together, you will have better brakes and no lights ever. Some describe this as slash and burn, that is fine. I got good brakes and no surprises.



James

Slash & burn-on, it woked for me as well!

 

[cojhl2]

I had this prob with my 90. First the Brake light in on cause the ABS light is on. My prob diagnosed to be the module behind the glove box. Replaced it and still a prob. (Followed Service Manual procedure)



Finally found a short in one of the two wires coming up from the speed sensor on the diff ring gear. Short was up around the front fender.

 

[jimnance]

Thanks guys, all good info. Just got the truck and this seems to be the only issue.



I pretty excited about the truck. I has "only" 130K miles, but was the same owner that purchased her new in 1993. Age and health made travel impossible for him so he parted with his baby. It looks like he took good care of her. She sure runs good, and can't beat the first gens for fuel economy.



He also had a full guage package, boost, EGT, tach installed, but no performance mods. He was obviously concerned about keeping her running good.



Here's a picture of the new baby.

 

[mysteryman]

The abs (anti stop brake system) system is junk on the first gen trucks !

I posted the solution to your problem a while back. take a look at my posts.

In short, remove the valve at the rear and unplug the computer behind the glove box. Problem solved , cost to fix is zero... Truck stops...

Thanks guys, all good info. Just got the truck and this seems to be the only issue.



I pretty excited about the truck. I has "only" 130K miles, but was the same owner that purchased her new in 1993. Age and health made travel impossible for him so he parted with his baby. It looks like he took good care of her. She sure runs good, and can't beat the first gens for fuel economy.



He also had a full guage package, boost, EGT, tach installed, but no performance mods. He was obviously concerned about keeping her running good.



Here's a picture of the new baby.

 

[markha1]

I had exactly the sam problem, fixed mine for about 30 cents and a little time. If yao want detailed trouble shooting info pm me and I'll be glad to help.

 

[jimnance]

Thanks, I've decided to do the slash and burn. Why make things complicated? I assume I'll find the harness for the ABS by looking under the dash behind the glovebox? Or is it necessary to remove part of the dash to get at it?

 

[bgilbert]

jimnance, to unplug the rear wheel antilock module behind the glovebox, you need to empty out the glovebox, then swing it all the way open/out of the way/down to the floor somewhat. Then you can access the RWAL module, unplug it and you'll never see the ANTILOCK light again. I just did this to my newly acquired 91. 5, I lossed the antilock light, but the BRAKE light remains. I haven't dug any further.

 

[1stgen4evr]

If you do the slash and burn, the complete job requires that the valve on the frame near the rear axle be out of the circuit as well. It will cause blockage and the back axle won't have much brakes. That is discussed in a post back a ways. Poor brakes on the back will cause over load on the fronts brakes and all the problems that go along with that. Search under my posts and ABS, that should get the old post. below is one---------------------------



I mentioned this a few weeks ago. I did away with the system all together. Some refer to this as slash and burn. Well everyone is entitled to their opinion and mine is that you are better off without the system on the truck. Check the archives and you will find that a good many have had scary incidents with their ABS. It is a very poor system and if you know how to drive the truck, you can do a good job of being the controller by how you apply the brake(s). Your brain is probably at least a hundred times faster than the controler on the system.



The reason I finally did away with mine was an incident where I slid through an intersection (complete with red light) somewhat sideways with a trailer pushing me along and only front brakes working. To make matters worse, I almost took the side off a patrol car in the process. When I got the whole thing stopped, he gave me a thumbs up and cruised on by. I went straight to a lift and checked to see what was need to eliminate the crappy system. Two fifty cent brass fittings that match the different metal lines at the valve that then fit one another and bleeding was all that was involved. I have the best brakes on that truck it has ever had. No light, no bull. Should the need arise, I can lock her down in a four wheel slide, and that ain't against the law anywhere. It is against the law to smack someone from the rear, whatever the reason. I am on the road around 80k miles a year and seems like there is someone fairly often that bumbles out in front of me. I am reasonable sure that earlier problems with my front rotors warping (more than once) was the direct result of poor rear brake function and that had cost a fair amount over the years. By the way, the previous owner had spent 1800 dollars at the dealer to make the rear brakes work. And they didn't.



So, you pays your money and you takes your choice, as they say at the carnival. That was my choice. Further, it has been documented in national publications that the abs system can be dangerous and has been the CAUSE of accidents where deaths were incurred.



First gen forever and ABS free as well.

James



Edit: Unhooking the controller will not complete the job. The truck mentioned was already 'unhooked' and still the problem of poor rear brakes.



--------------------------------------------------------------------------

The fix requires two brass fittings to connect the line at that valve and voila, done. You can take the valve off the frame or not as you please but the job is not complete till that is done.



James

 

[Jim McCarty]

Does this same fix apply to 2nd gens as well? I have a '96 with RWAL and the rear brakes are weak to say the least. Tried bigger wheel cylinders, etc. Seems like the abs is keeping it from doing its job.

 

[HRDROKN]

I have never been a fan of ABS since my racing days... . I want to be in control of my brakes, not some computer!



My anti lock speed sensor was broken on my axle so therefore was not working. Under heavy braking I would lock the rear WAY before I have achieved maximum front braking. So in all my wisdom (NOT) I picked up a new ABS sensor in an attempt to stop the rear from locking up. Well it didn't work... some other component in the system is still a problem.



So... how can i get the rear from, scratch that... How can I get increased braking performance from the front. Pads? Rotors? Other mods? Has anybody done or used a particular product that made a difference?

 

[jimnance]

That would be the valve that requires the special fittings to by-pass?

 

[dpuckett]

I agree with bypassing the RWAL module. It goes into bypass mode, cutting your rear braking power. I did it on my 91, and my pedal came right back to the top where it belonged.



WHen I went to the D80 (13x3. 5 vs 12x3 brakes; plus, I think the "new" ones are adjusted), I had to relearn to stop the old beast- I HAVE BRAKES!!!Oo. Oo. Still have yet to bypass the RWAL, but if the pedal starts fading, that will be my first task.



ANother option is to pull the dash fascia, and remove the brake and RWAL/ antilock bulbs from the message center. Wroks well if you are happy with your brakes, yet have to pass inspection.



ALso, if your "BRAKE' light remains lit, check your p-brake switch. Sometimes (esp if you have a manual) they get out of adjustment.



Daniel

 

[1stgen4evr]

JimMccarty



Sorry, I don't know much about the second gen trucks.



Jimnance



Look back for a post that shows pictures of the fittings. They aren't special, just stock parts from NAPA.



James

 

[HRDROKN]

Under heavy braking I would lock the rear <b>WAY</B> before I have achieved maximum front braking.

Thats when my ABS is not working... .



So bypassing the ABS module help me???

 

[1stgen4evr]

IF repeat IF the newer trucks are like the first gens, eliminating the ABS altogether will put you (through your foot pressure) in charge of the braking and the pressure will be what you apply front and rear.



I have no answer past that.



James

 

[HRDROKN]

IF repeat IF the newer trucks are like the first gens, eliminating the ABS altogether will put you (through your foot pressure) in charge of the braking and the pressure will be what you apply front and rear.



I have no answer past that.



James

James... I'm with you there! What I'm asking and not just you in particular, is with my ABS not working (not in the braking loop) I have way too much <b>bias</b> to the rear brakes! Yes, I can control it through my applied pressure, but I'm not achieving maximum braking efficiency.



I have no problem with bypassing the ABS controler, but it seems that most of you are doing this to gain braking bias to the rear? No? I seem to already have too much!



And I am refering to first gen braking... . "1992"

 

[EZGZ]

I did the slash and burn and am much happier with my braking.



Buuuuut I sure miss my cruise control... ... . ????



Any suggestions or should I start a new thread?



thanks

EZGZ