I've got a 97 F150 Lariat, Long Bed, Extra cab that I've spent a ton of money restoring. I love the truck but have had an electrical issue. Last fall the truck died and the dealership told me it had a bad fuse box and GEM module that had been compromised by water. They couldn't find a water leak and so I spent $700 replacing the GEM module and fuse box. I don't drive the truck much especially in the winter and a few weeks ago I went to start it and realized I had a dead battery. I jumped it, charged it and when I shut the truck off, the lights wouldn't go off and killed the battery again. Back to the dealership who told me I had a bad fuse box and GEM module again due to a water leak, they still can't find. I replaced the windshield as that seems to be the only other logical thing to do and was cheap and after much arguing the dealership is replacing the GEM and fuse box at their cost but won't take further responsibility for it. I've gotten mixed messages from other shops about the likelihood that there is a water leak especially since i have never had water on the floor and tried to find any evidence myself using a hose at multiple angles. Anyone else ever run into this issue or know if these things are prone to any water leaks in that area? At this point, I'm considering dumping the truck since I can't keep chasing this leak (if it exists) at $700 a clip.

 

Not sure where the windshield guy was looking, you would have to pull the A pillar trim cover, and the driver's side of the dash towards the A pillar where the hinges are at, to see if there is a leak.

Did you see the old GEM and fuse panel ? The only way to tell if this is the case, is to pull both of them, and unbolt the GEM from the Fuse panel. The pins between the 2 would have discoloration / corrosion on them.

The connector for the GEM to the fuse panel is directly molded into the back of the fuse panel and the GEM. This is how power is to the GEM ( after a fuse ) and back to the fuse panel in the case of items like the interior lamp control relay.

Water is usually not pooled on the floor, but the carpet and backing for the carpet are soaked after a hard driving rain. This is where the carpet ends on the fire wall, and usually can be found at the base of the plastic kick panel cover on the driver side ( usually have to take it off to feel the water ).

The other source I have seen is the power moon roof, if installed.

If the drain tubes are blocked, water will pool up in the power moon roof channel and work its way down the a pillar to the Fuse panel / GEM. Not sure if you have this option on your truck or not. If you do, worth a check to see if the drain tubes in the channel are both open, and clear.

 

Thanks for the reply. Unfortunately I am traveling and wasn't home when the safelight guy came to replace the windshield but my wife specifically asked him to take a look when he removed the old windshield. It was a reach but figured I'd ask since he was replacing it. After reading another thread on the site, it seems that many have had similar issues withthis bodystyle. Some have cited windshields as the cause as it seems like they are prone to losing their seal around the top of the windshield allowing water into the truck. Some suspect a body seam issue under the cowling at the back of the hood so I'll probably look at that possibility as well.

The dealership pulled the fusebox and GEM so I haven't seen the corrosion myself but they seem to have seen evidence of water and corrosion. I did look at the carpet at the firewall and pulled the kick pannel and see no evidence of any water making it to the carpet so I am at a loss. Might be that there just isn't enough water to make the carpet very damp.