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Hey all g0t a 99 F250 crew cab 7.3 PSD this morning 12:01 am my horn started to blow continuiosly (weather raining cats and dogs) soon as I opened the door it stopped. pulled the fuse and went back to bed. The truck started and ran ok. Same thing happened about a year ago and both batteries were drained replaced batteries had a gem modual replaced, then about 2 months ago batteries drained again tech said that the windshield and door rubber moldings were distorted letting water follow wiring into the fuse box? I fixed the molding and no problem till now.
I also found a problem with the Horns,blowing a fuse one terminal on low side was corroded horn not working I replaced it. Then I had problems with the glow plugs (hard cold start) found it to be the glow plug relay was burnt the large booted terminal came off in my hand when loostening the nut. Thought everything was fine. NOW THIS AGAIN HELP!!! THANKS DD