What can make the ASD fuse blow?

What exactly connects to the ASD fuse that can cause it to be tripped. Like what parts of the wiring harness should I be looking at to fine where it’s shorting to ground
If you're talking about the 20A Fuse #9 inside the PDC, that connects to two circuits and both are in the PCM. I'd talk with Mark @Wranglerfix at www,wranglerfix.com and get his opinion.
 
I am trying that and I’ve been going back and forth on these wires for a bit can’t seem to find anything. I’ll keep at it though
Your test light is lighting connected to battery positive? I'd focus on the PDC first. Unclip it so you can view the rat's nest that's underneath. This is a common spot for a break or a short. You'll be able to tell which wire goes to the ASD fuse from underneath.
 
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What made me suggest Mark at Wranglerfix is the 05/06 PCMs can develop a problem inside that, according to him, make it look like a .410 shell went off inside and short various circuits out. No clue if that's what has happened to yours but it's possible. If the fuse that is blowing is fuse #9 as described above, only the PCM (and the wiring between it and the fuse) could cause that fuse to blow.
 
What year TJ? What engine?

Fuse 9 is the main power that runs through the ASD relay (not the power that energizes it). So anything between Fuse 9, to the ASD relay and on the other side of the relay can cause that fuse to blow. In a 2006, +12VDC from fuse 9 powers the PCM, but it also goes through the energized ASD relay to the coil packs and all fuel injectors. A short in any of that wiring will cause the fuse to blow.
 

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What made me suggest Mark at Wranglerfix is the 05/06 PCMs can develop a problem inside that, according to him, make it look like a .410 shell went off inside and short various circuits out. No clue if that's what has happened to yours but it's possible. If the fuse that is blowing is fuse #9 as described above, only the PCM (and the wiring between it and the fuse) could cause that fuse to blow.
One could unplug the PCM with the same test light test to rule out the PCM.
 
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Your test light is lighting connected to battery positive? I'd focus on the PDC first. Unclip it so you can view the rat's nest that's underneath. This is a common spot for a break or a short. You'll be able to tell which wire goes to the ASD fuse from underneath.
Yeah I got the light connected to the positive battery terminal and the prong sticking into the Fuse#9 ASD 20A spot and it’s lit
 
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Here’s the light I have set up