Hi everyone

I recently just came back from a 4-month trip to my rx8 with its battery dead but after replacement, it is now not cranking. I'm pulling my hair out trying to figure out why it doesn't want to crank
My almost certain is not broken list:
Relays（I swapped them around the relay box but didn't get new ones but the symptoms are the same so I think non of them is broken)
Connections to the starter (I've cleaned them thourghly with alcohol and made sure they make contact)
Starter motor( I jumps the 12v main to the ignition 12v and the starter motor started fine)
Battery I've replaced the battery with a working from Toyota highlander

My potential things that are wrong from what I heard online but don't know how to test
neutral safety switch(It shows I'm in gear correctly but I don't know if that mean anything lol)
anti-theft system/immmobiliser (the anti theft light isn't on but I don't know if the key has enough battery)

Things of concern that I have noticed:
the number 28 fuse was blown when I checked(apparently it for the starter) and I have replaced it with a working one from the backup fuses in the passenger side fuse box)
the wires connections to the starter seem pretty corroded but I think I've done a good enough job of cleaning it by scraping but I don't know for certain that it is clean enough and I don't know how to test it
I don't know how to test for 12v ignition so I don't actually know if it providing 12v and just bad connection it actually just doesn't provide 12v

Any thoughts and suggestions would be greatly appreciated
Thank You!

https://www.reddit.com/r/RX8/comment...mped_pls_help/
Reddit post with a video of me trying to start it

 

Hi, if your starter fuse has blown then it's because to much current was going through the fuse, and you said the stater wires are corroded.
I would start by replacing your starter motor harness with a new one.