If the fuse keeps blowing, I'd triple- and quaduple-check every wiring connection and make sure I didn't have anything switched around, such as a light-sense lead plugged into the phone mute or that kind of thing (not that this particular kind of mistake would cause that fuse to blow, I'm just saying as an example). I'd check every wiring trace between the sled and the battery to make sure nothing is accidentally shorting.

Then again, it could have been something as simple as: You didn't disconnect the battery before attempting your installation. While wiring things up, if the wrong thing touches the wrong other thing when the battery is still "live", then the fuse could have blown without the slightest hint of trouble.

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Tony Fabris