Pesky Electrical Issue (Short?)

So, in the past few days I have went through 4 AM2 30 Amp fuses. The first day, I was out with a buddy on some trails and the truck just stopped running, I checked my fuses, and the AM2 (fuel, ignition accessory?) fuse was blown, which had been a previous problem a few months back when I installed some light pods, which I later removed. So I simply took out the heater fuse (the same type and amperage of fuse) and switched it out. Today while me and some buddies were driving around in the hills again, my AM2 fuse blew AGAIN, luckily I had a extra because I bought one while i was at Napa. To my surprise, when I tried to insert the new fuse it blew instantly, well I tried to put in the new heater fuse as well and it fried as well. I had some spare 4 gauge wire in the truck so I figured I would have to cut a piece off and jam it where the fuse was supposed to go to get home, when I tried to do that it zapped, and continued to zap everytime I tried it, but eventually it stopped. After it stopped I shoved a piece of the copper wire in there and the truck started right up, and I drove it straight home. Also I forgot to mention that I have a 12'' sub woofer and a 100W 20'' light bar. So I am guessing that somehow either through the headunit or maybe the subwoofer, power is going through that fuse and blowing it??? I read a few posts and I tried the 12v light method (the light will dim or brighten when you disconnect the shorted wire) and the light never changed when I disconnected my Sub-woofer, distributor or my injectors. I have 2 possible theories so far and here they are

#1 My remote wire on my head unit is somehow sending power back to the fuse (the AM2 fuse handles all accessories as well.)

#2 there is a wire SOMEWHERE that has bare metal on it that is grounding out and sending power back to the Fusebox. Everytime the fuse has blown has been when I am offroading quickly, I had driven for decent distances both days before I hit the trails. I suspect that the wire is bouncing around and zapping on some type of ground.


Please any help would be appreciated.

 

heres a pretty good page taken from the factory service manual about testing for shorts in a circuit

 

The AM2 fuse feeds the White/red wire that goes directly to the ignition switch. There should be no splices in that wire, at least from the factory. If the AM2 fuse blows with the key off there is a direct short to ground between the the engine compartment relay box and the ignition switch. If it blows with the key on then the it is the coils, the igniter and if a 4 cyl the distributor. Is it a 4 cyl with a distributor? if it is this kind of a "know" thing.
I would drop the knee panel and take a look at the electrical portion of the ignition switch and give it a wiggle and look.

 

I know it sucks when you're on the trail, but it is a very bad idea to jump a fuse with wire if its blowing every time you put one in. It means you have a direct short and risk electrical fire. Hope there's no significant damage. Good luck.

 

By now I wonder if all the arcing has not burnt things to the point OP now has a poor connection .

You do know just how lucky you are OP that your truck did not end up a pile of melted plastic and metal

 

Sorry I haven't updated this in a while, I removed my subwoofer and extra set of tweeters, and the issue has magically went away =).... It never happened when I had the subwoofer installed so I have come to the conclusion that it was the tweeters, also could've been a bad relay (which we replaced). My train of thought is that since I have a cheap head unit, somehow hooking up the two extra speakers some how caused power to go back to the AM2 fuse since it handles the accessory's.

 

I was sitting at a stop light one time and when I pressed the gas, my truck died. I could not get it to restart, even though all electrical in the truck was working. I had it towed to a mechanic and they discovered that the AM2 fuse had blown. They put a new one in and it started right up. They could not figure out what caused it to blow, but they suggested looking at the wires that run around the valve cover to the ignition coils. They thought that the heat from the engine could have damaged the wire loom and a wire could have worn and shorted to the valve cover. I tried shaking the wires and could never get it to blow the fuse.

I suggest looking at those wires and trying to find worn down wire loom.