Water leak now electrical/start problems

[ooo5]

I have had two different incidents in the last few weeks with electrical problems when it has rained. I know I have a leak in the back window seal and even the underside of my driver carpet is wet.

The first time my truck was engaging the starter by itself, the radio, locks, windows all did not work. From the research I have done, these are classic signs for the GEM module. Well it dried out and everything was fine for a few days.

NOW, all of the sudden, my truck would not start one morning. It spins over, all of the previous problems (windows, etc all work fine). But it will not start. I checked the fuel shutoff and bypassed it with jump wire, I replaced both fuel pump and PCM relays under hood. (they were both clicking after the truck would fail to start). Even the headlights come on and have a faint glow (keep in mind the switch is off). When I finally get it to start, it idles extremely rough and dies.

I should mention that I do have an aftermarket alarm/remote start installed, but since I am able to start the truck, I am not sure if this is to blame or not.

On my ignition, there is a blue colored plastic piece with a wire going to it that looks cracked. From what I understand, this reads the key chip. It has been cracked and has not been a problem before, but I do want to replace it just to make sure. Does anyone know what this part is? or where else I should start looking for a way to solve this electrical problem?

Thank you in advance for your time and help.

 

[SVT Phillip]

I know exactly the problem. Ur front windshield leaks, a common issue on 98-04 ford f150's. window leaks allowing water/moisture on the GEM module..

The same exact issues on my dads f150, my dad put a dehumidifier in his truck over night it sucked up over a gallon of water. It fixed the issue until it rained next week.. He replaced the front window hasn't had a single issue in like 5 months..

My buddies Lightning down the road from me was doing the same thing at the same time as my dads truck so I already knew his issue.. He took his GEM module out. He Cleaned it and it and it was ok until it rained again. He replaced his window the follow week been going several months no issues now..

 

[SVT Phillip]

I should add when the GEM module acted up it would try and start the truck with no keys would also turn the defroster and headlights on by itself from time to time lol.. It makes a lot of weird shit happen..

 

[ooo5]

Thanks for your reply! So it must still be the GEM module. Those are the exact symptoms I was experiencing last week, but this week when it wouldn't start or stay running and all the relays under the hood started clicking, I was worried it was something more severe. I will start taking the GEM out and apart this weekend and stick some Damprid boxes in there now. Thanks again Phillip!

 

[SVT Phillip]

No problem man.. And my buddies L had relays and everything under the hood clicking as well.. My dads truck wouldn't stay running either. But the only for sure fix was replacement the window.

 

[Jroc]

You can likely get your insurance to replace the windshield for free, especially if it's scratched up.

 

[ooo5]

Update: :/... Ok so the other night it started fine. Then it's back the next day. I took the gem apart and it seemed clean and fine. Plus my windows, locks, radio all work fine. But it still won't start, just turns over and if it does start it idles rough and quickly dies. The weird thing is when the key is in the "on" position after a failed start attemp, is when the relays click under the hood. And the box by the brake pump is clicking with the abs light blinking, but if I hold the brake pedal just a bit ( enough for the sensor) then all the clicking stops. Could this mean the abs module is bad? And if so, would that keep it from running or is this all a side effect of another electrical prob resulting from the leak? My floors were all wet.

 

[ooo5]

It ended up being a bad ground. Just behind the driver-side headlight there was an 8mm bolt that I took out, cleaned up with steel wool, and tightened. It solved the entire problem! And just to be sure, I disconnecte the ground again and boom! Same symptoms were recreated. It's crazy how something little like that can cause such a monster of a problem. Thanks all again for the help. I am still going to fix that back window leak so I ripped out the carpet and am giving it all a thorough cleaning.

 

[Robert Francis]

Good for you on finding that bad ground circuit! You're right - those things can cause all kinds of problems especially in this age of computer/sensor controlled opertions where voltage flucuations are significant.

Even back before computer controlled operations I solved many an electrical problem (after doing a lot of unnecesary things) by restoring good grounds in the electrical circuits.