Sorry for the long post... This just started this afternoon. Weather has been great out, I've washed my truck a couple of times over the last couple of weeks and no weird issues like this ever. Then today it rained and this afternoon strange things started happening. I drove my truck home and when I went to shut it off, the blower for the heater/ac kept running with the truck off and key out of the ignition. So I turned it to the off position and it shut off. Then I opened the door, and the door chime started going like I left my key in the ignition which it wasn't. Then it sounded like a bunch of relays were going ape***** under the dash. All kinds of crazy clicking noises and stuff. I called a mechanic I know and he suggested that it may be water leaking onto the GEM (generic electronic module). I googled and found that this has been an issue on some other ford vehicles along the rubber strip by the a-pillars. I pulled the strip and all looks good. I pulled all fuses cause after I got home and let it sit for about 20 minutes the horn just started blaring and then quit when I opened the drivers door. I looked around all under the dash and nothing looks wet. I can't see where water would be leaking in (of course it is a pretty cramped area). Anyone have any ideas?! Also, where's the GEM? I'm assuming it's not the PCM. I'm at a loss here. I just ordered my DPTuner too yesterday and would hate to not be able to install it because of these crazy issues. Any help is greatly appreciated!

 

the first things to investigate on a situation like this is any afermarket wiring 9 times out of ten its something hoaked togther as a result of modifications

 

I haven't done any mods that involve any wiring in over 8 months or so. And everythings been great til today.

 

The GEM is located on the backside of the fusebox. What you are describing is a classic GEM symptom.

 

yeh, sounds like a GEM module or water intrusion issue. Had one that would leak water into the connector on the back of the fuse panel,this of course would set of a whole world of electrical issues and never blow a fuse. Pull the fuse panel. its a pain. but pull the fuse panel and look for water in the connector or inside the panel itself.
Barney

 

So the GEM is located behind the fuse panel? I'm getting ready to take the truck to a windshield place to see if they can figure out where the leak is coming from. Once I get home I'll full the fuse panel (I'm assuming we're talking about the one under the dash and not the one under the hood). Would it be a good idea to cover the GEM with a plastic bag or seal it somehow?

 

I believe so. even if its not the GEM, if water is getting into the underdash fuse panel connectors it will allow voltage to complete the circuit without going through the fuse or the switch.
What part of Alaska?
Barney

 

Agreed

 

I'm in Anchorage. I took it to the windshield place and the windshield seal tested good all the way around. There was a hole in the firewall where some wires where running through, but it's been there for 2 1/2 years now. He sealed it on both side with some polyurethane. I pulled the fuse panel after I got home and pulled the GEM off the back of the panel. There was no signs of water getting into the fuse panel or the gem. I went ahead and wrapped duct tape all around the GEM except for where the plugs go. I sprayed the truck with the water hose too and couldn't see any signs of any water getting into it. I'm thinking of pulling the rubber seal off the doors and lining the inside of those with epoxy. Would this be a good idea? Any other places that you guys can think of where water may be getting into the under-dash area? Thanks for all your help so for!