2nd Gen Non-Engine/Transmission Brake and ABS lite on

[Houser]

Hi

Its about -30f and my ABS and Brake warning lights are on. They have been coming on during cold snaps for about 4 years now and I haven't really worried about it to much. When I got close to home tonight the temp was up to -6f and the warning lights were still on. Does any know what sensor might be causing this? The brakes get really stiff but work fine and the reservoir is full.



Mike

Palmer, Ak.

 

[robbiesworld]

On my 95 I found a relay that was marked "yellow ABS light" I took it out.

On long night trips the red BRAKE light was bothering me so I used black tape and covered it up

 

[Moe]

Hey Robbiesworld, where did you get those driving lights? MOE

 

[Mishkaya]

Hi

Its about -30f and my ABS and Brake warning lights are on. They have been coming on during cold snaps for about 4 years now and I haven't really worried about it to much. When I got close to home tonight the temp was up to -6f and the warning lights were still on. Does any know what sensor might be causing this? The brakes get really stiff but work fine and the reservoir is full.



Mike

Palmer, Ak.

Usually it's the rear wheel speed sensor that goes bad on you. It's located on the rear diff. Check the contacts first, then replace as needed. 95% of the time this corrects the problem.

mishkaya

 

[georgej]

Would the rear diff sensor cause just the red brake light to come on without triggering the ABS light?

 

[Mishkaya]

Would the rear diff sensor cause just the red brake light to come on without triggering the ABS light?

As far as I know, you will get both lights with the rear wheel speed sensor. Usually just the brake light tends to be low fluid.

mishkaya

 

[georgej]

Thanks, I've been trying to track down two gremlins( electrical I think). Engine hiccups and then later the brake light comes on. I disconnected the va smartbox and the engine miss has gone but the brake light comes and goes . Today I replaced the alternator brushes and cleaned grounds so I'll put a few miles on it and see...

 

[Houser]

Thanks for the tips Ill try replacing the speed sensor. And start working on my new cold WX related failure.



Mike

Palmer

 

[pcarlson]

Really cold temps mine will do the samething. Changing the speed sensor does not fix this but after it runs for awhile a restart will kill the lights. Only happens to me when it is really cold, below zero, and when the lights are on I have no ABS. As far as I know there is not a sensor for fluid level to cause the brake light.

 

[nutter3]

houser,
mine does the same thing. i have cleaned the connector to the rear sensor, that did not solve it. i will one day get a new sensor. or wait for this cold snap to end.

 

[cojhl2]

I had this a few years back. First, the brake light comes on if the ABS light is on. It is meant to be that way.



I followed the manual and ended up replacing the ABS module behind the glove box. That did not fix the prob.



What I found was a short to frame of one of the wires coming up from the speed sensor.

 

[pcarlson]

cojhl2, you bring up a good point. I remember seening something along this line about the wires for the rear speed sensor and it is not on a TSB but I believe that the dealers have a report on this very thing as something to look for if these conditions exist. I had completely forgot about this and will have to check my wires for a possible short. The cold could make these wires brittle and crack creating a short since these must flex and move with the suspension.



Good call as these could be a fix for some like myself where this happens often and one cannot go through that many sensors.

 

[JustinLee]

I had that several years ago during the summer in CA though. That was the precursor to one of my front hubs failing. The lights came on because the ABS sensor was actually melted from the failed bearing. That was in my '98. You'll know because the front end doesn't know where it wants to go.

 

[Grumpy John 4x4]

abs&brake light

Have the same problem, just found out on Competition Diesel [check your vaccum lines, they crack and break, if you have low vaccum they will come on, cruise will not work either, the ones-under the battery at the cruise actuator are very prone to failure] that was the answer I got, will check it out in the morning,Also found in my service manual to check the low vaccum switch mounted on the driver side fender panel .

 

[Gweeds12V]

I took a drive this saterday and those lights came on, my brake was hard as a rock and couldn't stop, i originally thought it was vacuum, its still in shop right now. They're saying its my fluids but i know they were right where i want them, full lol. Anyways i won't get the truck back until next week probably, they wanna test my brake fluid even though i told them to flush and bleed it anyways...

 

[cojhl2]

That pedal being hard and the brakes not working means the booster is not participating in the brake application. Probably a bad booster or a bad vacum supply.



I naver heard of fluid casuing this prob.