The overdrive switch and window fuses have blown on my 99 F150 the last two weeks. I replaced the overdrive fuse and it lasted a few days before failing again, I am replacing the window fuse today. I do have an Astro Start system on the truck. I am guessing there is a problem where the Astro Start is connected to the truck's main electrical harness. Anyone have additional ideas to trouble shoot this problem?

Thanks