High-mount brake light problem

[Chris Harrach]

Good afternoon. Have been having an issue with the High Mount Brake light for about a week. Seems that it only wants to work when IT wants to. It will come on, then when I push brake again , it wont. Unable to figure out what kind of light is in there because I cant get the lense out. All Ive found is a long metal box that has a plug and 2 wires coming out each side. I've taken it loose as far as I can, but Im coming up with no answers.:fire: Surly if I can replace and repair a Rack & Pinion as well as a complete rebuild of my rear differential, I can do this!!!!:scratch: Has any one on this forum had a similar problem with this and just HOW do you go about removing the lense??????? Any & all suggestions will be greatly appreciated. Thanks

 

[Dan Whitaker]

1996 & 1997 (& I think maybe 1998) use a ballast for the third brake light. You have to remove the rear hatch panel to access the light/ballast. Those ballast are quite expensive.

 

[Chris Harrach]

Thanks for the response Dan. So is the ballast that long silver box with the plug & wires, or something else? I know that a couple of times Ive fiddled around with the wires and even given it a good thump. The light comes on but only for the one time. Do you happen to know what kind of light this is? It has all sorts of warning labels. And could extreme heat cause it to malfunction? Its been brutally hot here in Georgia the last few months? Im grasping at straws here, but anything is possible. Thanks.

 

[snoranger]

Its a neon light, thats why it has a ballast.


Here's someone who "rebuilt" it with LEDs...

http://www.explorerforum.com/forums/showthread.php?t=146303

 

[Dan Whitaker]

Yes that long silver box is the ballast. There is a thread on the forum somewhere on it and the light.

 

[Chris Harrach]

Yes that long silver box is the ballast. There is a thread on the forum somewhere on it and the light.

Once again, thanks for the quick response Dan & snoranger. So I've located the balast (quite by accident I assure you), but Im having a time finding the disconnects for the wires that come out of each end. Ive also read on this forum that cleaning the trailer hitch plug will solve the problem. I'll go out and see if I have one & and give it a try as soon as the temperature drops below 90 degrees ( it was 104 about an hour ago!!!:fire Hopefully it works. If not, its off to the "Pull A Part" to see if I can find another ballast. By the way, I read that there is a fuse back there but I cant figure out where it's located. Any ideas ? Thanks again.

 

[Dan Whitaker]

I don't know where the fuse is. I was lucky and never had a problem with mine. I sold my '97 Mounataineer last year as it was starting to have sevearl small issues and after 10 years ow owning I needed somethng newer & different to play with.

I hear you on the heat. It's been above 100 here in Kansas City the majority of July. We had maybe a 1/4" of rain last night and it's in the 90's today but the humidity is high. Can't win for loosing.

 

[Chris Harrach]

I don't know where the fuse is. I was lucky and never had a problem with mine. I sold my '97 Mounataineer last year as it was starting to have sevearl small issues and after 10 years ow owning I needed somethng newer & different to play with.

I hear you on the heat. It's been above 100 here in Kansas City the majority of July. We had maybe a 1/4" of rain last night and it's in the 90's today but the humidity is high. Can't win for loosing.

I know what you mean about the heat. I went to Miami over the 4th of July week end holiday, just to get away from the heat and the INfamous Atlanta humidity. It was hot there as well, but I had the ocean to swim in and lots of cool ocean breezes. Gotta go back real soon. I hope I can get this light problem solved soon as I consider NOT having the high-mount brake light a safety issue. I have to do a lot of driving around with a 3 year old & her 6 month old brother. And Atlanta has some of the WORST drivers & traffic in the nation. I need all the safety features working on my ride.

 

[Chris Harrach]

High-mount brake light problem (update)

Well I found the trailer hitch plug located in the rear bumper, just as I read on a thread titled " Third brake light not working " from 2008 & 2009, courtesy of gmanpaint & NJMikes. It's just a plug with 4 wires going into it, with a grey cover on it. The connectors are dirty, but I dont see how a "Dead End" plug going to nothing can effect the Third Brake Light. The other end of this wiring harness goes to the driver side tail lights. There I found a large plug, so as soon as I get the proper electrical connector cleaner, I'll go and clean BOTH of them off and see what happens. In the mean time, if anyone knows where the 10 amp fuse going to the High-Mount Brake Light ballast is located, please let me know. I'll post again as soon as I see if this "Spray & Go" method works. Cheers.

 

[Chris Harrach]

High-mount brake light problem (2nd update)

Well I went & got a can of CRC "QD Electronic Cleaner" at O'Reillys auto parts. I've sprayed all the connections that have anything to do with the High-Mount Brake Light, including the plug that goes to the high voltage ballast. Nothing exploded or caught fire which I took as a good sign The High-Mount is working, but it remains to be seen whether or not this "Spray & Go" solution actually solves the problem. Yesterday, when I found & inspected the trailer hitch plug, the light started working again, and continued to do so until about an hour & a half ago. It had stopped when I went to O'Reillys for the spray cleaner, but was working again when I got home. Ive since cleaned all connectors. Im still not 100% convinced that this damn heat-wave that we're having doesnt have anything to do with it being on the fritz, but hey, what do I know. I'll keep my fingers crossed to see if this works. Hopefully this is the last time I have to be bothered with it. Cheers! And try and stay cool.

 

[bobflood]

Chris - fellow Atlantan (well, Powder Springs) here. Mine died about a year ago and a bought a replacement ballast/light assembly from "kbabiak" on this forum. Mine turned out to be the ballast, so that is all I changed out. If I had it to do over again, I would buy one of the LED replacement lights and get rid of the ballast and neon light completely. Good luck.

 

[Jstcruz]

For future referance; The 10 amp fuse is wrapped in some black rubbery crap between the ballast and the harness from the truck. Its just a small fuse holder.

 

[Chris Harrach]

High-mount brake light problem (2nd update)

Chris - fellow Atlantan (well, Powder Springs) here. Mine died about a year ago and a bought a replacement ballast/light assembly from "kbabiak" on this forum. Mine turned out to be the ballast, so that is all I changed out. If I had it to do over again, I would buy one of the LED replacement lights and get rid of the ballast and neon light completely. Good luck.

Hey there Bob! Good hearing from you. Let me ask you this: When you changed yours out, where did you disconnect the ballast at? Did you have to cut & splice the 2 wires going into the ballast on the right side? If I have to eventually switch the ballast, how do I disconnect those wire's? Ive looked to see if there is a plug or something, but Ive yet to find one.

 

[bobflood]

Hey there Bob! Good hearing from you. Let me ask you this: When you changed yours out, where did you disconnect the ballast at? Did you have to cut & splice the 2 wires going into the ballast on the right side? If I have to eventually switch the ballast, how do I disconnect those wire's? Ive looked to see if there is a plug or something, but Ive yet to find one.

There is a plug on both ends of the ballast. I don't remember if the ballast was in the body or the hatch (it sux to get old and febble minded!). When I removed the old one, I pulled out enough wire on the "input" side and there was a plug. Unplugged old ballast, plugged in new one, and away it went.