ABS and Brake light on

[Posm]

Yesterday when I was driving down the Interstate, the ABS and Brake light came on. The brakes appear to operate normally and the fluid level has not changed. I checked for leaking wheel cylinders and ther does not appear to be any fluid on the wheels. I only have the rear anti-lock brakes. I unhooked the battery to clear the code, but it came back on within 10 seconds of start up. Any help short of a dealer visit would be helpfull.

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Y2K 2500, QC, 4X4, 3. 54LS, ST, 5 speed, SWB,Cummins E-brake,Westech Pyro and Boost Dual guage, 12 Disk JVC CD

 

[Dieselnerd]

Mine did that while still on warranty. Exact same symptoms. It was the sensor pickup in the rear axle housing. It unbolts from the outside without opening the "pumpkin". Tech checked it out with a meter but I don't know what to meter for since I saw him do it from a ways off and didn't talk to him later.

 

[samb]

the same thing happened to mine. 5* dealer charge 60 bucks to check out and 34 for the sensor.
Sam B.

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97, Lamanie SLT, clubcab, driftwood, 3. 5 spicer 70 rear axle
96 Coachmen Royal 285rk 5th wheel, 11,000 #

 

[Happy Camper]

I had both those lights come on when the fuses were blown. Simple and less expensive than having the sensor go out.

 

[illflem]

This probably isn't your problem but my '95s ABS and brake light will come on when the washer fluid light comes on and not go off until I refill the reservoir and disconnect the battery. Computer glitch. My solution has been to keep the reservoir full.

 

[John HBD]

Posm, If it has less than 36k let the dealer fix under warranty. Check the fuses first,if they are fine measure the resistance of the sensor in the rear axle. Unplug the sensor and measure across the two terminals inside the sensor. The resistance should be about 1200 ohms, if not replace the sensor. You did not say if the speedo was erratic or not. The speedo receives its input from this sensor. Good luck

 

[Posm]

I did not notice the low speed speedometer loss until after I had psted the topic. Today I wnt to the dealer and got the sensor for $34. 00. The truck shop machenic saw me as he was leaving for the day and said it should be no problem if the stem does not break off of the sensor. He told me it happens some times. His remedy was to take some snap ring pliers and open them inside the stem and wiggle it out. He was very helpful and gave me his card and wrote his cell phone number on it just in case.
The old sensor was tight, but I took it easy and twisted it around and pried gently on the base until it came out. I put a little grease on the O-ring of the new sensor and put it back in. I removed the battery cable to reset the computer and everthing was fine when I started it back up. Everyone at the dealer was knew about this part, which leads me to believe that it goes out often.

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Y2K 2500, QC, 4X4, 3. 54LS, ST, 5 speed, SWB,Cummins E-brake,Westech Pyro and Boost Dual guage, 12 Disk JVC CD

[This message has been edited by Posm (edited 05-05-2001). ]

 

[Alaskaskiff]

I got the same light combo when The vacuum hose on the fire wall came apart. Brakes weren't noticeably diminshed, but 4x wouldn't engage.

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Andy Raiha


96/2500/4x4/4. 10/5sp/CC

 

[Joe G.]

I've had this problem for quite some time now. I changed the sensor with no effect. Then I thought it might be vacuum but couldn't find a problem with that either. Upon closer observation I have determined that it will come on if the truck is sitting still and running for some time. A stop light can be long enuff to cause it. I can prevent it from coming on by creeping a little while waiting for the light. Increaseing the RPM has no effect so I think that would rule out vacuum. Any ideas other than the **** thing is haunted?

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Joe George
Eureka, CA

'95 2500 CC auto 4X4,3. 54,Combo EGT/boost guage,custom switch panel,PacBrake,TST #5,DTT TC/VB,Automatic motorhome steps on both sides,Foldacover hard bed cover,Cummins chrome kit,Black steel grill guard,Front hitch receiver

 

[maint.man]

Joe, Mine did the same thing exactly. After racking my brain I finally gave up and went to my local Dodge dealer. It turned out that it was a wire under the dash. I know the repair was less than 80 bucks and I was told that letting it go can lead to failure of the ABS controller. (not cheap) Also one last thing to check would be at the connector by the bumper where the tail lights are wired in, mine was corroded beyond belief. Hope ya' get it fixed, I know how annoying those lights can be.

 

[Cooker]

Mine will do it occassionally too, but mine is a bit different than the rest.

After the truck sits, usually overnight, the lights will come on shortly after startup. And stay on until the truck is turned off and restarted. Also I haven't noticed it at all after it has started to warm up.

I'll have to do some digging I guess after reading some of the fixes posted here.

Ryan

 

[John HBD]

Cooker, You do not say what year your truck is. The ABS system changes from year to year and whether it has 4-wheel or 2-wheel ABS. I can explain how to retreive codes on 97 and earlier and what the code means.
John

 

[Cooker]

Sorry it is a 96. As far as I know it only has RWABS.

 

[Bob V]

This morning my truck did exactly what Cooker's truck does. Mine is a '97 with 4 wheel ABS. I instaled a Pacbrake just before this happend. Any ideas?
Thanks, Bob V

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'97 CC 5spd 4. 10 5spd 315/75 16,Bushwacker,TST 280hp.

 

[Joe G.]

maint. man,

Do you know which wire it is? It must be what is wrong with mine. My ABS (RWAL only) has not been working for some time so the symptoms fit. I don't really care about the RWAL, but the light is a PITA and I would sure like to fix it.

I don't really have any corrosion in any wire connectors. No salt on the roads or snow for that matter.


[This message has been edited by Joe G. (edited 05-08-2001). ]

 

[DOWG]

My truck used to do the same thing with the addition of an erratic speedometer. Pulled the rear wheel sensor and found a flake of metal stuck to the sensor. Cleaned the sensor, pulled the differential cover to check for damage; everything ok. The ABS and brake light still came on occasionally. I have since installed the Abbott EPRA to correct my speedometer to account for the 19. 5 Ricksons. I spoke with the folks at Abbott and I reset the dip switches on the EPRA to increase the signal strength to the ABS module; the lights went off and have been off ever since. This leads me to believe the problem is due to a weak signal from the rear wheel sensor to the ABS "brain".

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1998 Driftwood Extended Cab,Short Box,12 Valve,4X4,Auto,Dunrite TC,3. 54,Banks Plate,AFC Spring Kit,Isspro EGT,Rickson 19. 5's,Abbott EPRA, Rancho Shocks,Heim Trackbar,Mag-Hytec transmission Pan & Pumpkin Cover,Amzoil Synthetic's,Ranchhand Bull Nose Front Bumper, Headache Rack,Tool Chest,Side Steps,Rear Bumper and 100% Stock Airconditioning.

 

[maint.man]

Joe, sorry I can't help ya' on the wire location. It just got to the point where I couldn't take it any more and I said fix it. If I'd count my time worth 10 bucks an hour that I spent it was cheaper to let DC get it. Sorry , but for what it's worth I haven't had a problem since.

 

[Joe G.]

Ok, maybe the clue is enuff. At least you are the first guy that has any idea what to fix. I'll get the wiring diagram out this week and identify the suspects. Might get lucky. Thanks for the info, maint. man. #ad

 

[tron1959]

Mine was a 94. Dealer changed sensors twice, no luck. Then I took it to the dealer in next town. Service manager told me what it was over phone. He ran the wire from the rear sensors to the computer (new wires) separate from the harness and used a pair of wires and twisted them. Supposedly the brake light wire was inducing a very small current in the sensor wire causing the computer to sense a fault. The computer never set a hard code that could be read. This fixed it.

 

[Joe G.]

Mine always sets the code for a high resistance connection. It will do it even if the brake has not been touched so the brake light circuit is not involved with my failure. Very interesting fix. I can temporarily set that up and see if it fixes my problem. The fix may be correct even if the diagnosis was not. Thanks TDX2 for another clue. Maybe I can fix this aggravating PITA afterall.