Electrical problems after heavy rain
New User
Joined: Sep 2015
Posts: 7
Likes: 0
I had the same issue. I got a 99 f250 5.4. Every time it rained hard the truck would freak out. The transmission would rev up high and shift hard. The speedo would bounce all over the place. My aftermarket radio would stay on after key is off. And the dome light would short out but be on with door closed and make that buzzing sound on the fuse box. I figured it out. The fuse box gets water logged or water damage (grounded) since u saw water on your floor mat. Unhook the negative terminal on battery and put a fan on the fuse box under the dash for 24 to 48 hours and put silicone on every window and seal, I put flex shot clear silicone on everything even some cracks on the roof. Put it on the windshield seal and on the cover for your sprayer washers all the way across and rear window and 3rd brake light. Blow some compressed air in your passenger transmission harness, unplug it first, mine had water in it. Maybe put some air on the fuse box to. I did all that and it hasn't failed me yet. A fuse box is about 400$ on ebay. Ouch just imagine how much it is at the dealer. Hope this helps everyone. It helped me
Cargo Master
Joined: Oct 2011
Posts: 2,874
Likes: 768
From: SoCal/Wyoming
I had a similar issue with my 99 f250 after it rolled over a few times and they tried to fix it. Puddle of water under brake pedal each time it rained, shift problems, light problems, and even my alarm would just go off driving down the road. No rain...no problem. Traded it back in 01 for the one I have now. You might call safelite and see if they can come out and take the windshield out and re-seal it. Should be much cheaper than getting a replacement and that way you know it's done right....just an idea
Senior User
Joined: Jul 2018
Posts: 192
Likes: 6
This is an old thread but am having similar issues. Windshield is now sealed tight. Took fuse box out and cleaned all terminals. Everything is dry yet the relay still buzzes. It stops as soon as you turn the dome light on. When dome light is not turned on and doors closed, it buzzes. Replaced the relay and no joy. Not sure where to attack this from now.
Suggestions?
Thanks
Suggestions?
Thanks
Senior User
Joined: Jul 2018
Posts: 192
Likes: 6
Update. Pulled fuse box out again. Took apart, cleaned, sanded, soaked in vinegar the whole nine yards. The gem module has zero evidence of water in it. Put box in and seemed to work great. 20 minutes later, after we left. dome light comes on. I only know the time by reviewing a video surveillance camera that shows the truck at night.
Open door and key in ignition bell is dinging. This happened overnight and now battery is dead. Started truck and lights still on.
However, seemed like slamming door had effects.
Any thing in the doors that might be suspect? Power window or lock? This thing is kicking my rear end.
Thanks for any help
Open door and key in ignition bell is dinging. This happened overnight and now battery is dead. Started truck and lights still on.
However, seemed like slamming door had effects.
Any thing in the doors that might be suspect? Power window or lock? This thing is kicking my rear end.
Thanks for any help
Cargo Master
Joined: Oct 2007
Posts: 2,712
Likes: 107
From: BoCoMo
Update. Pulled fuse box out again. Took apart, cleaned, sanded, soaked in vinegar the whole nine yards. The gem module has zero evidence of water in it. Put box in and seemed to work great. 20 minutes later, after we left. dome light comes on. I only know the time by reviewing a video surveillance camera that shows the truck at night.
Open door and key in ignition bell is dinging. This happened overnight and now battery is dead. Started truck and lights still on.
However, seemed like slamming door had effects.
Any thing in the doors that might be suspect? Power window or lock? This thing is kicking my rear end.
Thanks for any help
Open door and key in ignition bell is dinging. This happened overnight and now battery is dead. Started truck and lights still on.
However, seemed like slamming door had effects.
Any thing in the doors that might be suspect? Power window or lock? This thing is kicking my rear end.
Thanks for any help
Door switch for the 'light' and 'door open'.
bad contacts and 'staying on'... imo
New User
Joined: Dec 2018
Posts: 1
Likes: 0
My truck just recently developed this leak issue. Its happened twice now. I found that mine was a cab light leak. The first time it happened my blower motor would stay on with key off and the speedo would act crazy and my o/d light would flash. Well this past week it done all the same things except out of nowhere my trans just started this growling noise in overdrive only. So i fixed my leak and let my truck air dry. Took it down the road last night and everything is working fine except as soon as my truck goes into o/d it starts growling. Is this probably water related or does this sound like a coincidental trans issue at the same time as my leak. Thanks in advance guys
Lead Driver
Joined: Sep 2010
Posts: 7,793
Likes: 50
Some players in this thread....MMMYERS, id say coincidental just like when i did the ccv reroute. Next day the dipstick flange started leaking.
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New User
Joined: Feb 2019
Posts: 1
Likes: 0
Again, beating a dead horse...
Yesterday, it rained fairly hard for most of the day and was around 60°f. Overnight, the temperature dropped to around 20°f. After driving my truck multiple times throughout the day today, I had no issues other than my injector pressure control sensor that I had diagnosed a few days ago. After shutting my truck off after driving home from work at 11pm, I noticed the passenger airbag light was on, blower motor never shut off, and there were relays going crazy. After pulling the fuse box, I didn't find any water but slight traces where water had been where the left harness connects to the fuse box. Currently crossing my fingers it's just a leak from the clearance lights which I already know have a leak but I couldn't find anything damp. Going to try to reseal the lights and drown the connectors in dielectric grease. Fuse box is currently sitting on my radiator in the house and the gem is airing out. Only source of transportation other than the racecar which is not a fan of snow or rain for that matter lol. Commenting to hopefully help someone else as you have all helped me .
New User
Joined: Mar 2020
Posts: 3
Likes: 0
After Heavy Rain Phantom Issues with Fan, Radio, Starter Not a Leaky Windshield
I have a 2000 Ford Expedition I bought for my 17 year old kids. I noticed a dead battery after some heavy rain. Further investigation was the radio, fan blower, and even starter turning on when the keys were not in the ignition. I thought it was a wet GEM but I had the windshield checked and it’s not leaking. Could it be the black plastic tray at the base of the windshield? I read the foam disintegrates and it seems to have. I’m sick of having to unplug the battery before each rain and need to get this figured out... Suggestions?
Hotshot
Joined: Mar 2014
Posts: 10,750
Likes: 1,065
From: Douglassville, PA
I have a 2000 Ford Expedition I bought for my 17 year old kids. I noticed a dead battery after some heavy rain. Further investigation was the radio, fan blower, and even starter turning on when the keys were not in the ignition. I thought it was a wet GEM but I had the windshield checked and it’s not leaking. Could it be the black plastic tray at the base of the windshield? I read the foam disintegrates and it seems to have. I’m sick of having to unplug the battery before each rain and need to get this figured out... Suggestions?
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Aug 25, 2011 11:58 AM