Brake lights don't work

[bmaguire36]

Help! My brake lights don't work. But the third brake light on top of the tail gate does work.

The bulbs are good, the fuse is good. The brake switch works.

Another thing is that when I put it in drive and take my foot of the brake the doors should automatically lock. They do not anymore.

Any ideas?

-Brian

 

[Brian36]

I searched the web and someone else has the same problem. See http://www.startribune.com/stories/432/405074.html

It was suggested that it may have to do with TSB 97L13. Something to do with a bad install of the aftermarket tow harness.

I don't think this applies to me as mine was factory installed.

The dealership wants $97 hour to look at it.

Has anyone had their brake lights go out (but not the third brake lamp) and/or the automatic door locks not work when you put it in drive and take your foot off the brake?

-Brian

 

[hijinks]

I have with my bronco. But mine didn't have the third light. Ford had some messed up wiring in the bronco and not sure if it's the same with the X. Their wire went up to the front flashers and then back to the brake light and back flashers.

When I list both of my back brake lights after wondering for hours what it could be I had someone turn on the flashers and the back flashers worked but no brake lights or tail lights. The problem was one of the front flashers bulbs was dead. I changed that and it worked.

To make a long story short.. Check all your lights to see if maybe Ford did the samt wiring for your X as they did in my old bronco. Its better then paying 100 an hour.

 

[Brian36]

Thanks, I'll check all bulbs this afternoon ....

 

[Brian36]

I fixed it! Using the schematic I found where the 3rd brake light wire splits off from the main brake light 12 volt switched wire. I knew that the problem (break or short) was after that point since the main brake lights did not work but the 3rd did.

Turns out the 3rd brake light has its own fuse, the main brake light goes to the incoming side of the fuse but then continues on. That was where the break was.

To fix it I ran a 15 inch wire bypasssing the inaccessable fuse box. The wire is tapped in the switched side of the brake light switch and runs into the light green wire in the cable harness below the fuse box.

How did this break happen? I forgot that the Explorer is basically a car that looks like a truck and when I was fooling around I ran the driver side front tire up on a pile of dirt in my driveway making the car twist. This must have put undue stress on the tight wiring harness and popped off the wire.

-Brian

 

[dwk55]

Brian36,

I think I have the same problem with my 97 mountaineer.

Where exactly is the fuse / split for the 3rd brake light located?

Thanks

 

[Brian36]

DWK55,

So your 3rd brake light works but your regular brake
lights do not, right?

If no brakes lights work then it is most likely your main brake fuse. If just your 3rd brake light is not working then there is a fuse just for the 3rd brake light.

In my case the 3rd worked but not the regular brake lights.

The bulbs, fuses, and brake pedal switch were good.

It had to be a short or broken wire. A green wire runs from the kick plate next to my left foot under the inaccessable fuse box all the way to the back. The wire was not shorted. I tested this by cutting the wire AND removing the bulbs then checking it to see if it shorted to ground. I should have got 12 volts from the upper side of the whire that I cut that came from the fuse box and before that the brake pedal switch. I was not getting the 12 volts. The wire must have poped off the back of the fuse holder during my twisting the truck. Of course I can not visually check this.

I ran a bypass wire from after the brake pedal switch using an inline crimp connector up and then down behind the kick plate in into the green wire that runs to the back.

It took many hours to trace, test, and verify where the problem was. And about 15 minutes to fix it.

-Brian

 

[dwk55]

Thanks,

The 3rd brake is working, but not the regular brake lights.

It sounds like I will have a good project for part of the day.

I will let you know how it turns out.

 

[dwk55]

I think I found the cause. Both bulbs are burnt out. Makes me wonder if there is a short some where. For a while the horn didn't work, but now it does.

Only time will tell.

Thanks for your help.