Blowing AC1 Fuse

Hey guys, hoping for help from some of you regarding an issue with my 1997 4runner 4x4. I've only owned it for about 4 months and up until now it has been reliable. However about a week ago while driving to work it just stopped running. I managed to coast to the side of the busy street I was on, but it stopped running so suddenly it was like someone flipped a switch. Once safely to the side of the road I was able to determine that the battery was strong and that all the accessories still worked, but when the ignition key was turned the starter would not engage. After I got the car home I was able to determine that a fuse in the engine side fuse block, labeled AM2, was blown. I obtained a replacement fuse and installed it, but when I tried to start the car the starter engaged and the engine actually ran for about two seconds before blowing the fuse once more. Obviously there is a short somewhere. This circuit seems to run the coils, injectors and engine management, but I'm getting in over my head beyond that. I'm actually not to bad on circuitry on older cars, but these newer ones leave me scratching my head. Anyone got an idea where to start looking first.

 

I would find a wiring diagram instead of just guessing where to look.

http://www.teamtoyota4x4.org/archivio/1996 to 2002 Toyota 4Runner Repair and Wiring Manuals/techinfo.toyota.com/ileaf/ewdtmc2/ewdtmpdf/ewdsourc/2002/024runne/overalle/overalle.pdf

Just making sure which fure. Your title says AC1 but text says AM2.

You sure nothing else is popping looks like a pretty hefty power fuse.