I've read most all of this thread, starting to sound as if maybe many of these are problems with the plugs on back? Maybe a better support of the harness would help?

I do like the idea of some dielectric grease in there to preserve the contact points. I know I had mine out once to replace the info center illumination bulb .... was a lot of "plug" there.

Electrical gremlins are, I believe, most often the result of bad connections. Back in Feb 1986 the wife and I went out on a limb and bought a near new 1985 Thunderbird, we loved the car. A few weeks after purchase, it started with this habit of just suddenly cutting off. Engine would just die ..... and as you coasted, suddenly pick up and go again. Might not do it for weeks, then again. Ford put several EGRs on it, spent hours on rotunda, all under warranty .... no cause, no fix.
One day I was determined, either fix or trade .... I took a small itsy bitsy screw driver in hand and pulled every single connector under the hood, one at a time, and tightened up the female part so it better gripped the male part and applied dielectric grease, reconnect, and to the next one. Took a good while.

Never again did that car so much as hiccup on us, we added TC front bumper and fog lights, AA rear deck spoiler and end wraps, Konis, wheels, gas, oil, etc .... and we kept it until October 2009. We both get pi55ed to this day when we see it now and see how dirty and uncared for it is with the current owners .... if I could do it over we'd still have that one, we'd just have 7 Fords and a Forester.

But I digress ..........

 

I have a 2006 F-150 XLT 4x4 with 148,000 miles on it. My red brake light has been coming on also. Mine will come on and stay on until I turn the truck off. When I start the truck again the light is out. It will come on without warning. I haven't had time to do much diagnosis yet. What I have done is verify the fluid level and checked the parking brake switch. The issue I am having seems different than others. My light comes on and stays on, it does not go on and off intermittently and it does not come on right away when I start the truck. I am going to be replacing the front calipers, rotors and pads within the next month or so because the L/F caliper is starting to hang up and prematurely wearing out the brake pads and both rotors are worn out. I will also be flushing out all the old brake fluid from the entire system (front and rear) as well when I do the front brakes. I don't know if this is going to solve the brake light problem or not but I will certainly report back with any news on it after I do the brakes.

 

I had the same problem as all of yall. And I spent a wail reading though all of this and do research on it and it can only be three things that cause the brake light to come on and stay on. The three photos below are them first you want to check your e brake by pushing it down then finding the switch and pushing it in all the way if that doesn't turn off the light you'll need to check your brake fluid levels and sensor you can check that by unplugging it. If that doesn't fix it your problem is like mine and is in the cluster in your dash and that could cost a lot of you pay someone to fix it, but it's not hard to take it apart once it's apart I played with it and found out if I push down on the terminal block the light would turn off so I got creative and used a piece of tie wire to hold it in place and it's worked. I posted a you tube video to show you what I'm talking about just look up 2006 Ford F-150 how to fix e brake light that won't turn off

 

looked for your youtube fix, can't find it. Can you post the link? thanks

 

Just fixed mine today (2005 XLT). My light has been on for a year now and when one of my caliper pistons busted I decided to research this light issue and get it resolved. Thats when I came across this thread and the issue is the plug on the cluster. I used a soldering iron and re soldered the pins that were mentioned earlier in this thread I think it was pins 1,2,3 and 17. I didn't know which was pin 1 for the start so I did the first 3 pins and the last 3 pins on each end of both rows.

My brake light is off now and only time will tell if this a permanent fix.
Hope this helps

 

Thanks for this post! I fixed my son 01 F150 dash by re-soldering colds solders jounts (Gray colored)on the Cir. board and now everything works on it. I will do this same on mine (re-solder the pins) 04 f150 Stx Light has been on forever!

 

Can someone post or send me a schematic of the cluster circuits? I want to solve this once and for all. My issue is not the in the solder connection (I re-solder all of them already) but in the connector itself. I can apply pressure and see the light come on and off. Since I can't get into the connector I can bypass somehow if I can see the schematic. 2004 model please

Thanks

 

I wonder if one of the clips that slide over the pins inside the plug is broken and not making a good tight connection???? We have to find out which pin number it is. A schematic of the cluster circuits is a must at this point, unless someone knows which one it is??? anyone?

 

Here is another idea to the problem. In this video of removing the cluster, these plugs have a gray plastic rotating clip that holds the plug tight in its socket, What if because of the heat from the sun on the dash, weakens the gray plastic hold down from holding it tight? Any idea's are good at this point because 04-08 all have the same brake light problems and we all want to fix it for good! Thanks (How to remove your 04-08 dash video)

 

FYI: If you guys go with the re soldering be sure to use a magnifying glass to check for bridging or your problems could get worse.

 

Updating on what I have found out about this problem and fix(at least in my case).

My brake light was always on but nothing was wrong like many others out there. Unplugging and plugging it back in only fixed it for a brief drive before it came back on again. Next I did the re-solder thing. I didn't know which pin was which nor could I see any cold joint under a magnifying glass, so I re-soldered them all. Again lasted for a drive and it was back on again. Lastly tried applying pressure to the harness connector and I could make it come on and off with pressure which signify a cold joint but I have already re-soldered twice already. Tried applying pressure to the wires themselves and could see it mess with the brake light consistently thus leading me to think the harness was bad.

After thinking about it further this doesn't make any sense as these connectors have a very long pin and is secure their entire life. It’s not like they are being pulled and put back all the time or expose to the elements. Heck a lot of clusters out there with the problem have never been unplugged since leaving the factory. Lastly, why just the brake light? Wouldn't the other circuits using the same pin and harness system have problem too? So I discounted the notion that the harness/wiring is the problem and look elsewhere.

Upon studying the schematic for the cluster with regard to the brake circuit I could understand how it works and thus we don’t need the schematic for what is in the cluster (not that we are ever going to get that info).



There are two separate circuits in the cluster involving the brakes. First is the emergency/foot/parking brake and this is on pin 24. This is a normally open circuit so a cold join/break in the wire will NOT turn on the brake light. We can ignore this circuit all together. If you are having problem with the light not coming on when the pedal is down then check/adjust the switch.

The second circuit is a closed loop circuit on pin 2 and 3. This is where we are going to focus on. From the schematic we can see that it is a closed loop circuit and probably being held high and going low during a fault condition. This is indicated by the switch in the brake fluid reservoir. From this we can extrapolate that any break in the loop will cause the brake light to come on. So a cold joint or broken wire anywhere in the circuit to pin 2 or 3 will cause the light to come on. We know this because if the brake fluid level drops too low, the switch goes to ground thus bringing the loop down to ground….0 volts. A break in the circuit/loop between pin 2 and 3 will also mean 0 volts to the monitoring circuit in the cluster thus causing the light to come on. You can simulate this yourself by disconnecting the harness at the brake fluid reservoir. Base on this info there can only be two things that could cause the light to come on, a break/cold joint en-route to pin 2 and/or 3 or a bad level switch.

The switch is easy enough to troubleshoot. Just pull the harness and check to see if pin 2 and/or 3 on the switch has continuity to pin 1. If it does then the switch is bad. Just make sure your fluid level is not low when checking.


Ignore the bypass jumper I added for testing



Break in the wiring (harness) I already discounted so that leaves us with cold joints which is a little more involved because we have to take the cluster apart. First thing to try is to re-solder pin 2 and 3 on the cluster. See the pictures and diagram below to locate the pins. If that doesn’t work then you will have to take the needles off to get to the other side of the circuit board. This is where I believe most if not all of the problem lies. I was not able to locate (too old, eyes aren’t what they use to be) exactly which component(s) it was that had the cold joint but it is one or more of these. I re-soldered the components inside the red circle but I believe the culprit is probably somewhere in the blue circle. I re-soldered all of the components but ignored the IC, transistors (3 legged) and the really small components. This fixed my brake light problem for good.



One word of caution though. These are small surface mounted electronic component and thus do not need a lot of heat. Hitting them with a really big and hot iron is probably not a good idea. I design electronic circuits and make my own pcb at home so I have the proper soldering equipment. Not sure what everyone has for a soldering iron so be careful. Not enough heat is bad but too much heat could be worse.

Just sharing what I think is the problem so take it for what it is. Mine is working for a couple of weeks now. Light only comes on when it is suppose to when I step on the parking brake.

 

Just an update my light came back so I'm going to try dvo1's repair when I get the chance. I hope it will be this weekend.

 

Had the exact same issue with my 06 5.4 screw XLT. Brake light was illuminated and seemed to go off and on as it pleased. I was also due for an inspection and would not pass with the light on so one day I stopped at my local ford dealer and asked if they were familiar with this issue. Apparently, its common and the tech told me he has seen it a few times and said it was a soldering issue. He then proceeded to tell me that a new XLT dash would cost about 600 from the dealer, LOL. Of course I passed and he gave me a card for a tech that use to work for ford and went into his own electronics business and would be able to solder it. One day while scheming on eBay I came across a 2008 FX4 cluster for 65 bucks. Read 100k on it (close enough) swapped them out, which took 15 mins, and plugged it right in. Had to take keep the transmission part from the XLT since the the FX4 is in the center console but no biggie two clips held it in. Solved the brake light issue, looks a hell of alot better with the way the dash is set up and it flows nicely with the vent covers. Mileage is a bit off but I'm not selling this truck so its fine by me, so it you can find something close in the miles or youre not worried abut that maybe you can find one from another truck, just dont buy one from a ranch or lariat. I believe they have a climate sensor or something like that and might not work right from what I remember but double check that just in case.

 

Hi, I have been having the same problem with my 2004 F-150. I just changed all the brake pads, fixed the Emergency brake(s), changed a caliper, changed the brake fluid sensor and connector, WTF??
I haven't yet tried changing the e-brake sensor, that is my next option.
If anyone comes up with more ideas I would really appreciate them, I was lucky, my regular mechanic wouldn't pass my inspection due to the light, but I found another who was aware of the situation and gave me a pass.

 

As others have noted, the problem is typically in the gauge circuit board. There is a cold solder that causes a break in a circuit. Ford wants you to replace the gauge board -- at a cost of several hundred bucks.

My 2005 had the problem intermittently -- right up to the minute that I traded it in.

I love Ford trucks - and currently own 3 of them, but when I went to buy a new one last winter, I definitely thought about going with Dodge or GM (and test drove their trucks) - because of Ford's unwillingness to stand behind these faulty safety components.

The good news? I live in Denver and there used to be a guy who advertised on Craigslist that he'd come to your location, repair the board/wiring for about $150. Cheap compared to Ford's fix.

Haven't seen his Craigslist ad lately, but I believe there are firms who will do the repair if you send them your board.