You need to explicitly identify your vehicle including whether it's a US or international model.

 

Thanks for all the assistance with this issue. Of course everything I tried nothing seemed to work. Ended up paying a Ford mechanic to come by after work and look at it. After a couple hours of troubleshooting he found the problem. The brake lights, turn signals, horn all run through the speed control servo. It apparently got moisture in it and shorted out. Good thing was all he had to do was unplug it and the brake lights and turn signals started working again. I can either replace it at a cost of $400 or leave it unplugged. I don't even use it so I wont be replacing it.

 

Actually, they don't run through the servo, but they run off the same fuse. If you'd followed my instructions several weeks ago, your brake lights would have been operating all this time.

 

I have a 1996 F250 and lost the brake lights last week. I traced out all the wires, verified all grounds and even ohm'd the wires, fuses and switches suspecting a break in the wires or a bad switch. Frustrated I resulted to google and found this thread. The one place I didnt check was the MFS switch, a quick tilt up of the steering wheel made the brake lights work and conformed the MFS. Thanks again for keeping this thread live. It helped out a lot

 

My signals work, but none of the 3 brake lights work, replaced the 15 a fuse for brakes under the dash and they work for like 15 minutes and then it blows again, also the ABS light flashes on the dash AND I can't start the truck until the key is turned a little and the shifter gets put to neutral, then I can shift, otherwise it'll start in park, but then I can't shift to drive or reverse to move

 

Sounds like you need a new brake light switch.

 

Hello. I bought a 2010 F150 SUPERCREW XLT with 80k miles last month. I am having the same problem with my brake lights and rear directionals not working. I read the other posts and tried tilting the wheel and securing wires on the MFS switch but it did not work. What does work if I shut off the car and restart it will work for a while then I will notice the fast blinking light on dash when I am signaling. Sometimes just right, sometimes left and some times both. The cabin break light always works. Any suggestions?

 

Welcome to the site, Sullyjj; congrats on the truck! I recommend dropping by your local Ford Dealership so they can check out those misbehaving lights. Once you've had them take a peek, I'll be able to research some options to help.

Crystal

 

thanks for keeping this up. I have no brake lights or running lights or turn signals in the back. I did go through some deep mud holes but my high brake light works? I did pull the two covers off the steering column and did see a loose red wire and i pushed it back in and still no brake, running, flash or turn signals? Any suggestions? did ohm the bulbs and checked the fuses and that all seems good even put new ones in just to be safe? Any help would be greatly appreciated. After I pushed in wire on steering column my hazards and my adjustable brake pedal started working (hazards didn't work in back only side mirrors and front)

 

I would start with checking the ground at the rear of the truck.

With all the lights out at the read, the common is ground G104, which shows as by the left ( driver's side ) front radiator support.

Ground G103 is on the right side radiator support, and is for the front lights.

If memory serves me correctly, this is in the wiring harness that is above the spare tire along with the trailer tow circuits.
- Been some time since I had my 2001.

If you drop the spare tire, you should see the rectangle connector.

One quick test, before dropping the spare tire, is check the bulb connector with a meter for + VDC using the trailer tow connector ground.
- This is terminated on the left rear frame.





There could also be the issue with the wires pulling out of the MFS ( MultiFunction Switch ) that you appear to have found one issue with.
Some times raising the steering wheel all the way up will release the pressure on the harness and the wiring will make contact again. This is the connector shown in post #5 up the thread.
- I this could be a side issue, as you have not parking lamps in the rear and the common point with parking lamps and stop & turn lamps on both sides is the ground.

 

Thank you I'll check the bulb connection with a meter and the connector above the spare tire. It all happened after I went through a pretty deep mud hole coming back from my tree stand and I guess I hit the brakes coming in or going out of mud hole that was pretty deep. Thanks for the illustration and direction I'll be sure to post results. Thanks again for the insight

 

Hello fellas, I read thru and found valuable info here.
What puzzles me is that after replacing the (BOO) and checking the fuses on my 2000 f150 4.6l, my brake lights still do not work. My tail lights work, but no brake lights. Pepboys doesn't want to touch it, and THEY told me its some short.
HEEEEELLLLP!!!

 

Sorry for posting to an old thread but this seemed like the best place to seek guidance that I've seen yet. I have an 07 FX4 and recently have had a lot of trouble with my brake lights as I've been trying to convert my lights to LED's. The lights originally worked well, but after about a week of full conversion, my fuse #2 blew twice, since then I upped it to a 30A fuse and it hasn't blown again (not sure if that is part of the problem or not). Now, my brake lights don't work except for my third brake light overhead. I've done everything from taking my steering wheel apart to check my MFS to replacing the brake switch above the brake pedal. I've just run out of things to look at and I'm not very electronically savvy so besides paying someone else to look at it I'm not sure what else to look at. Thanks for any help!!

 

Starting a new thread would have been better, considering how far apart the model years are. Next time go that route.

What was the LED conversion that you did ?
- Is it LED with built in load resistors, or external load resistors. Link to the parts or kit would be great.

Installing a fuse 50% too big is not a good idea, you might want to pull that out and put the 20A fuse back in, and reinstall the factory tail lamps.
- The wiring for the Stop / turn and the MFS contacts are not designed for a 30A load.

You have to high of an AMP draw from the LED kit, or there is a high resistance to ground short. Both of these look similar from a fuse blowing stand point, but diagnoses they are different paths.

If your CHMSL ( aka Center High Mount Stop Lamp / 3rd bake light ) still works, the Brake Pedal Position Switch ( what a BOO is called now ) is working correctly.
The output of this has a slice that feeds the CHMSL and the MFS ( for the rear lights ), so you know to this point is still good.

When you checked the MFS, what did you do ?

The other thing to keep in mind, is the Stop / Turn might be working to the rear of the truck but the LED lights you installed are not changing brightness in any meaningful way, making it appear that they are not working anymore.

I would pull the LED kit, and test at the rear of the trunk, with a meter, for the functions of stop & turn.

At the rear bulb connector:
1. Ground is the black wire ( not always the case, but here it is )
2. Parking lamps is the Brown Wire
3. Left Stop / Turn is the Light Green w/ Orange Stripe wire and Right Stop / Turn is the Orange w/ light blue stripe wire.

Meter from ground to each function to test.
Best to test brakes ( on the wire #3 above ) on both sides, as well as test for the turn function on each wire ( using the turn signal, not the 4 ways ).

In short order, get the 50% too large fuse out, before any thing else happen
- hopefully nothing bad has happened already EG: melted wires.

 

What sscully said. REMOVE that fuse before something melts

I bought and installed LED bulbs and an electronic flasher in my 03 (yes I am aware they are different animals).
They worked fine for 3 days, before the drivers rear decided to short out internally causing all of the parking lights to flash when the lights were off. I sent them back and reinstalled incandescents in the rear. If you bought cheap bulbs you may be experiencing the same kind of problem I had. Oddly enough the LED's I put up front are still working fine, the brake/turn function must've been too much for those "cheap" bulbs