DISCLAIMER: I did this and didn’t think to take any pictures so I went back and took some until the final step which was the most difficult. I didn’t want to sacrifice my efforts and mess something up by redoing that part so I tried to describe it as best as possible.

I have a 2004 Ford F150 4.6L V8 4X4 Supercab. I developed a problem with my interior lights where they will come on randomly while I was driving. After many hours spent searching for an answer online, I found this thread:

https://www.ford-trucks.com/forums/9...e-driving.html

What I picked up from that thread that was helpful was that if I tapped next to the dimmer/light switch panel my lights would go off.

Since all of the interior lights go through the instrument cluster I figured I would start there but it proved to be fruitless.





The next step I took was to look at the wiring diagram for the interior lights and try to figure it out there. They proved helpful in that I was able to figure out that it wasn’t an issue with a relay or fuse and led to me looking for the Green/Orange circuit, which I discovered I don’t have but pointed me towards the Black/Blue circuit.





I thought I might have a wire loose inside the light switch so I started to remove it and take it apart to hopefully find something.
To remove the light switch place a flathead screwdriver under the panel and pop it loose.








From there you can get a finger underneath and pull it out completely
Next you’ll want to remove the wires by pressing on the clips pictured below





There are three screws you need to remove to get to the circuit boards underneath








Removing the actual light switch was tricky because there are two tabs pictured below and you have to finagle the switch out








Once you have that removed you’ll be able to see two clips at the very bottom of the switch enclosure. This step was very hard and I had to get help. The two clips at the bottom have to be pushed and you have to pull the circuit board at the same time. I chose to have my assistant push from the bottom while I pushed the pins out of the way.





Once you have the circuit board out you can remove the dimmer by pushing on these four tabs





Once you have this removed you will see a circuit board with some gel on it. My circuit board had an excessive amount that was causing the electric current to jump and by-pass the Dome Defeat. After removing some of the gel I reassembled and put back in. I did it earlier today and only time will tell if I truly did fix it but based off the amount of gel and my inability to find another cause I am hopeful that this was a fix. The dimmer appeared to work better immediately afterwards.

Hopefully this will prove helpful to someone as I have been unable to find an actual fix to this problem. If you have any questions please feel free to ask and I will try to help if I can.

 

How long ago did you remove the gel from the light switch? Is it still working correctly

 

I did it yesterday but it started to work immediately. My interior lights would come one as soon as soon as I would start the truck and randomly while turned off. Last night I didn't notice the lights coming on at all.

 

I did notice today when I tap near the light switch the dome light would go off. I can also tap on the dash above the instrument cluster and the light would go off. Keep me informed if what you did fixed it. I will check my light switch out this weekend

 

Are you lights still working right ??

 

I haven't noticed them coming on while I was driving or while parked. I think this may have fixed it or at least it contributed to the problem and fixing this was helpful.

 

Did this fix end up working out? My truck is having the same issues and nobody has a straight answer of what's wrong with it. I have a 2006 F150 with a 5.4


Dome light will come on and off randomly... the vehicle can be running or parked outside at night. I can tap the dimmer/light switch panel and it will instantly kill the dome light off.
I found the other thread that points towards replacing the instrument cluster.... Did this fix work for you or do I need to replace the instrument cluster?
The local Ford dealership is claiming they have never heard of this issue before.... the first thing they want to do is talk about door switches... they will not listen.


Before I go spend money to have this fixed I want to make I know what's wrong before they start ringing up a bill. Please HELP

 

Hopefully the OP will chime in.
Certainly seems like the switch is the likely cause. It looks like the dielectric grease starts to breakdown and conduct. I would try spraying the switch with degreaser and see if it solves the problem.

 

I replaced the light switch and still have this problem. Tapping in the dash and slamming the door, wd40 doesn't work. I finally have just left the dinner switch in the off position. Which makes seeing the dash lights at night difficult. Would it be wiring?