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urgent: tracking brake light problem before Mustang Week!

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I know the whole brake light thing has been hashed to death over the years, and I've googled & searched the crap out of it.  I REALLY need to get this taken care of before we leave for Mustang Week on the 11th, so this is where I'm at... I really appreciate y'alls help!


car is a 2004 GT with auto trans...


I have lost brake lights and shifter stuck in Park twice in the last 10 days.  I thought I fixed it the first time, but it's back again.  



* no brake lights, and no 3rd brake light

* shifter was stuck in Park

* replaced brake light switch, and it didn't fix anything.

* tested oem brake light switch and it was still good

* found fuse 33 was blown, replaced it.  brake lights came back, but shifter was still stuck in Park

* removed shifter trim, and dicked around with the shifter... got it unlocked.

* drove away assuming we fixed it.



* at gas station, shifter got stuck in park again.  Brake lights also gone again.

* I removed shifter trim, and dicked around with shifter to unlock it.

* In the fog of war, I broke the little cable that comes from the neutral safety switch.  So now I can put it in gear without pressing the brakes.

* drove the car home, inspected fuses.  Found fuse 33 blown again.


* replaced fuse 33 and still no brake lights, still no 3rd brake light either.

* fuse 41 is good.


So here are some things crossing my mind...

1. Does the neutral safety switch also control brake lights?  Since I broke that cable, I technically have not "unlocked" that switch yet.

2. Since my 3rd brake light doesn't work either, does that rule out having a bad multifunction switch?

3. I have read about "the ground in the trunk"... does it also control the 3rd brake light?  If not, then does that rule this out?


We are going to the in-laws for Holiday festivities, but I'm going to get back on it Sunday.

I'm going to run a tester through the fuse box, maybe my new fuse is faulty?  I am open to ANY suggestions... I need to get this fixed before the 11th!  


This sucks because I've been busting ass for the past month to tie up loose ends for Mustang Week.  Pretty much got everything taken care of, but then this pops up at the midnight hour.


thanks guys!

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usually the brake fuse #31 blowing is due to the clutch pedal rubbing through the wires.  I just read that yours is an auto.  Not sure if it's the same thing - sounds very different.  Consider this a bump for help!

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I just wanted to update this, just in case anyone searches for this topic down the road...  you won't believe what was causing my problem!  My driver side a/c vent was sweating condensation, and it was dripping down onto my fuse box... thus blowing the brake light fuse.


To be more specific, it would only sweat enough to actually drip if I drove for over 1.5-2 hours in humid conditions.  Then it built up enough condensation to drip onto my fuse box.  Those one or two small drips landed right where my brake light fuse is.  I assume any adjoining fuses didn't blow because they are constant "hot" and likely evaporated the small amount of moisture before it could cause an issue.  But the brake light fuse only goes "hot" when the pedal is pressed... so the moisture just sat there on that fuse until I pressed the pedal... then POP.


I began to track down that possibility because I was driving with flip flops on one day and felt a couple drips of water on my ankle after driving a long trip with the a/c on during a hot humid day.  Then I could feel moisture on the top of my fuse box with my hand.


So basically I have not had any brake light issues since this discovery, as I made a little ghetto shield to cover the top of my fuse box.  Just thought I'd share for others!

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