2nd Gen Non-Engine/Transmission Abs/red Brake Light

[JWaters]

I saw my ABS light flash on and off today leaving the Gas station, after flashes it stayed on and will not go off, The red brake light is on also. This is the first real problem with this truck ever, It is a 1996 dually with 81,000 miles on her. I have owned her since new! What should I look for? and how do I check the codes?

 

[Cummins Thunder]

Sounds like an ABS sensor has gone out... .



My ABS light will come on if I play in the mud, but usually turn off within a few minutes of getting back on the highway.

 

[FourBarR]

abs sensor on rear diff. top left side.

 

[tURBOdIEZEl]

i had the same problem. do your brake lights work? reason i ask is because when i encountered the same problem as you my brake lights would not respond. the solution to my problem ended up being the abs fuse located in the cab on the drivers side. i kept popping fuses untill i put a larger one in and have not had problems since.

 

[JWaters]

all fuses are ok, brake lights work, cruise control doesnt work... but it stop orking last week this week the abs/brake came on.

 

[tURBOdIEZEl]

you might need a new abs sensor located in the rear end...

 

[JWaters]

do you think cleaning it off and putting it back in will work?

 

[MHalloran]

do you think cleaning it off and putting it back in will work?

JWaters, yes try cleaning it first. Had the same happen to me,(on my 96) came on then stayed on . Happened during winter when wet, first time after 180,000 miles. Took it apart, cleaned it up, fine since. No more brake light/abs light. Good luck. Mike

 

[CEpp]

clean it or replace it. mine did the same at 120k, replace and no problems

 

[JWaters]

Ok went outside and cranked up truck, light not on anymore... so I went ahead and backed it down the driveway and jacked it up, took out the sensor that was not dirty at all and cleaned it off more. Put it back in and cranked up the truck and bam,,, the light is back on... . so I guess I need a sensor! I was suprized that the sensor was so clean when I took it out.

 

[WBusa]

I've had the same problem off-and-on: intermittant brake + abs light. No telling when it would go on, and would go off only after shutting off the truck. The problem was rare... only every few weeks, maybe, but each time for a couple of days at a time.



I replaced the rear speed sensor, but that didn't solve the problem. Then, one day, working under the hood, I noticed that the main vacuum line attaching to the hose barb next to the master cylinder was a little looser than I liked... the hose was stretched pretty wide on the barb. So I cut off one inch of hose, then worked like the devil to get the fresh hose end back onto the barb. Problem solved (I think?)... its been about two months now since those lights last glowed at me. I can't claim that this really did solve the problem, mostly because I don't understand my brake/ABS/vacuum system very well. But I'm cautiously optimistic... .

 

[Driftwood Ram]

I'll vote for check vacuum lines. I was having problems with the ae-brake and the abs/brake light was sometimes on. When I got the vacuum issue with the e-brake fixed, the light issue stopped also.

 

[JWaters]

well this morning i cranked it up and the abs light was off i pumped the brakes and the light came back on. I shut it off and cranked it back up and the abs lite was off again, pumped the brakes and it came back on, I have followed the vaccum lines and they all look new and no split ends, I pulled one line off and there is a good suction on it. I let it sit and pulled the main line to the booster off and vaccum release from it. I dont really understand this yet?



I have noticed one thing, if you let it Idle and you pump the brakes 3 times, the first 2 times it has brakes the 3rd time the pedal is hard and there is now brakes. I think something is wrong here as with the engine idleing it should have brakes all the time. Why after 2 pumps they are gone and then the 3rd pump the pedal is hard and then you can feel the booster coming back as vaccum builds.



What does everyone elses truck do? do you all still have brakes after 2 pumps?

 

[JWaters]

abs

ok after reading alot of post in the search area, I went outside and took out my brake light switch, pulled the plunger out and reinstall the switch so it can adjust its self, well not the cruise control works now. It works even thought the ABS/Brake light is still on. I thought it would not work if the abs light was on?



The Cruise works



The ABS light is on



The Red Brake lite is on.



I cleaned the ABS sensor in the rear(even thooght it was already clean)



Where do I find the dianostics plug for the ABS inside the truck?



What does it look like and how do I get it to pull up codes?



All Vaccum lines are good and it holds vaccum even after sitting for a long time.



Any more suggestions??

 

[GAmes]

Do you have a brake controller? If you do, unplug it and see if the problem goes away. If it does check the two wire bundle connectors behind the drivers side front tire, one of them might be full of water.

 

[Fogie]

When I did all of what you are doing with my 99, I went thru the same procedure. I found that the brake light switch is not adjustable or reuseable. Replaced the switch with new and no more problems. Cost me about $15 at the dealer. Be sure to follow the instructions in the package. They can only be set once. Good luck!!

 

[JWaters]

ok unplugged the trailer brake harness, still same thing, check wires and they are clean and dry.



HOW DO I CHECK THE ABS COMPUTOR????



does anyone know??

 

[JWaters]

why can they only be set once? and why will it make the ABS light come on?



I pulled the plunger out and reset the switch, and now the cruise works but the ABS light is still on.

 

[JWaters]

Also I just noticed that if I hold the brake pedal down hard it will start easin off and I can feel it slowly going down, it will not go to the floor but it goes down till about 2 -3 inches from the floor but I have to hold it down hard.

 

[MHalloran]

JWaters,, did you get this ABS/brake light problem solved yet? Mine came on again :{ on my 96 5-speed (191,000 miles). I was at a red light & started off from a stop. Upon acceleration (kinda heavy) and runnin' through the gears, the lights lit up and have been on constantly. My vac lines all seem OK. Suggestions?