HI please help if you can
I have 1999 ford f250 superduty 5.4 v8 I noticed that my tail lights were not working I replaced the fuse as it was blown break lights worked until i cranked up and applied brakes.
I replaced fuse again an checked brake lights they worked fine until i cranked truck and applied the brakes i did notice the wires were hot at brake pedal switch when they worked while not cranked.I replaced the cruise control release switch I was told that may be the problem since cruise didnt work. it fixed the cruise control but as soon as i pressed the brakes fuse blew again.I replaced brake pedal switch didnt fix it.
I then noticed a little smoke under tailgate i looked and the wire coming out of connector was hot while brakes applied and not cranked. i disconnected that wire put a new fuse in and brake lights worked in center light and passanger side without blowing fuse driver side however does not work. Because i disconnected the brake light wire to driver side green wire.
when i re connected the driver side brake light wire fuse blew.
So I have it narrowed down to driver side brake light. here is my problem.
I have checked all the wires that i can see for bad or frayed /worn naked places i have found none I can get to the wires beside gas tank running the rail to check but it is doubful that it is spot as nothing is rubbing along there.
could it be a relay somewhere? can i just run a new wire from brake light?if so where to i connect to? is there a wiring harness i can just buy and replace the brakelight wires from brakelight to power source I have ran out of things to check on my own Please Help!

 

It's either the bulb, the bulb socket, or a chafed/stripped wire that is shorting to the chassis. Last one I had, a mouse had eaten insulation right behind the taillight assembly.

 

I removed the bulb wasnt it I will inspect the bulb socket closer tomorrow i will update you if i find something

 

try this had kind of same problem my trailor tow socket got moisture, salt ect in it from age made all my signals , brakes . blink and blow fuses, ATfirst thought turn signal switch and replaced it did not fix . traced it to back of socket

 

Ok checked bulb checked Sockets all good however i noticed that the wire causing the fuse to blow was spliced into my brake light wire so i removed the spliced wire and all lights are working i tested and all are good! fuse is good.

I think the spliced wire was for my electric brake trailer connector i checked trailer lights and they work the 2 other wires coming out of trailer connector
one is blue one is white the blue seems to be connected well but the white has a connector that looks like a ground connector and is not connected but it does look like it has been burnt. I have brake lights working on truck I will investigate the trailer connector and post reply i need to find out if the white wire is suppose to be grounded and what the spliced wire was actually for.