so i noticed today that after my truck is shut off for some reason the blower keeps going. I've had the truck since last april and it has never done this before. The truck came with an aftermarket stereo in it and my dad thought that it may be the wiring somehow got messed up? i would really like to know any possibilities because it ran my battery dead last night lol. if you have experienced this or know of any causes I'd be thrilled to hear them

 

I have two ford trucks, a 1999 F250 superduty and a 2003 F150 King Ranch. My F150 did this after a rain sporadically at times. Other times it would do other quirky things instead of the blower motor. Mechanic thought it was a ground issue and looked for a problem there. I finally figured out that I had a tiny leak in the windshield and moisture was getting on electronics under the dash, specifically the GEM module. A new windshield fixed the problem. I never actually found water puddled up anywhere. Hope this helps. It was my experience anyway. I DO know that it is frustrating.