Antilock brake light and brake light on

[Hemijoejr]

Ok guys ang gals I have another question for you. I am working on the same 89 dodge W250 w/auto and 4wd. The antilock brake warning indicator and the brake warning indicator comes on now and again. Are there any common problems that I should know about. I bought a Chilton's manual but for a diesel it is pretty much useless.



Thank's again

Joe O'Cone

 

[BushWakr - RIP]

Hi Joe,



Have you tried checking the elect. connector on the rear diff. I believe that there is a plug connection there that can get pretty corroded and gummed up.

Pull it apart, use lots of elect. spray contact cleaner, dry it out and apply some dielectric grease, and re-connect.



Also, check your brake fluid resevoir to make sure your fluid is right up.

Are you having any problems with the brakes themselves? Do you have higher than normal brake peddle travel?

Check vacuum lines from the vacuum pump to the booster.



Run a trouble code check... .

Turn the key to on/off, on/off, on. . then wait.

Watch the dash light on the right of the speedo. It will begin to flash on and off with pauses between each series. . like this... .

three flashes / pause / two flashes... long pause..... 4 flashes / pause / 4 flashes..... long pause.....

That reads 32 and 44 codes.

When the codes are finished running, you will get 55. That indicated "end code sequence".



Run that to see if there have been fault codes stored. Do not disconnect your battery or you'll erase any stored codes up to that point.



Bob.

 

[Philip]

The brake warning light means a imbalance between the front and rear brakes. This switch is activated by a loose of pressure in one of the two circuits.



Check fluid levels in master cylinder.



Look for leaks in the system.



Does the pedal creep down to the floor whenever you hold firm pressure on it? If it does and there are no leaks then the master cylinder is leaking internialy. Replace it.



As far as the ABS system light I need to dig out the manual and do some reading.



Chiltons manuals have been about worthless for the last 20 years or so. IMHO

 

[scotmartin]

Ohm out the rear ABS sensor. It should be about 1300 ohms. This is a very common problem.



Scot

 

[RGT]

on the '92 and '93 you can check for ABS fault codes by grounding the RWAL diagnostic connector, The ABS electronic module is located behind the glove box, the wire that you need to ground ground runs out from this and is just tie wrapped or taped to the harness just below it. Watch the amber antilock brake light and count flashes, count the long initial flash along with any short flashes... ... tell us what you find

 

[sparks57]

That's funny... in my truck the two brake lights come on when I hold the brakes at a red light (only accasionaly) or pump them when I'm standing still. It is also accompanied by a hard brake pedal.



What's the deal? I notice that my break fluid reservoir thing by the firewall straight back from the battery is only half full. Is that the problem?

 

["Mad Max"]

CB

Same thing happened to me - hard pedal, light on, and scary 6500 lb diesel rolling along with 'no brakes' feeling. Not fun. Come to find out that there is a little pod right under the drivers side hood mount brackets with a little vaccum hose going to it. Problem was the little plastic nipple that is supposed to be part of the pod was sticking out of the hose, and I had a big vacumm leak. Well, I took off the pod, got a generic plastic nipple from local parts store that matched the hose, epoxy'd the nipple back on,..... and that ended my brake problem. Cost about 25 cents - my kinda fix!

So, I'd check all of your vacuum hoses and trace the system off of the vac pump and up around the brake booster. You'll probably find something where it shouldn't be.

Good luck.

On the ABS thing - don't have any advice.

- Sam

 

[sparks57]

Thanks a lot, I'll get right on it.

 

[Jim Fulmer]

Ohm out the rear ABS sensor. It should be about 1300 ohms. This is a very common problem



Had the same problems and mine read out open... . R&R fixed it right up!



Jim

 

[Stab]

Check all your grounds, even the mounting for the box located behind the glove box. Unplug the control box located behind the glove box and leave unpluged for several minutes with the ignition OFF.



It seems sometimes these things gather static electricity and it starts to throw them off. I've done this several times over the years and it has cured many but not all.



All the above items should be checked if this fails to cure your problem.

 

[JLEONARD]

My lights have been on for about 6 months... ... (lights on, nobody's home)

As far as I can tell the brakes are working well... . next time I'm on the lift I'll check the diff sensor... everything else has checked out ok.

 

[skobylenski]

I had the same thing happen last fall. I was worried at first, but like you, JLEONARD, it didn't seem to affect anything. Eventually, I decided to check the fuse box, and lo-and-behold, a lot of the sockets were loose. They are only sheet metal that is bent, so they seem to loosen occasionally. Take a pair of needle-nose pliers and bend the loops back into the little tabs. This is awful to describe, just look at it and you should see what I mean.



I'd never thought to check the diff. When I do the self-adjusters on the rear brakes later this spring, I'll check that too.



Good luck,

Scott

 

[JLEONARD]

Scott,

I guess I'll have to take a peek inside the fuse box and see what's up. Thanks for the tip.

Jay

 

[skobylenski]

Yeah, its one of those STUPID things that you never think to check. It took me forever to think to do it myself.



Scott

 

[sparks57]

I went and checked all my vacuum hoses and even had a friend (who knows a lot more than me) check them and we both concluded that they were all tight. I asked if maybe the vacuum pump was going bad, or maybe that it needed to be turned up or something (if it even can be) since it only happens at idle.



Any suggestions?

 

[Hemijoejr]

The nipple was broken on the pod on the fenderwell on this truck too but all I did was block off the vaccume line. What does that pod do? That's what I thought was the problem with the brakes which it was but both lights still come on. I will check out the diff sensor and if that dosn't work I will check the rest of the system.



Thanks People!!!!!

Joe O'Cone

 

["Mad Max"]

Not sure what that pod does, but after I 'rebuilt' it all the lights went away and the brakes were much improved. I could hear the vacuum leak otherwise, so not sure if your brakes will get better.

Sam

 

[Philip]

That little thingy mounted by the left side hood hinge is the vacuum cut out switch. This will drop your cruise controll if the vac system goes below 8 pound. If you by pass it. Most likely your cruise will not work.

 

[Paychk]

Couple other functions are to turn on the brake and RWAL brake warning lights!

 

[Paychk]

I just noticed something that may have a bearing on the diff sensor. The wire bundle that connects to that sensor is called out in the wiring diagram as "twisted pair" this is a feature to minimize electrical interference. Any repair made to this bundle should be completed in such fashion as to maintain this twist all the way from the connector under the dash, back as close as possible to the sensor. If it is not, the bundle can act as an antenna, picking up interference and confusing the RWAL computer.





(edit clarity)