Here are the measurements. I still can’t red exactly the schematics, and I found any .brd file to upload on openboardview. I tried to be as accurate as I could!
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Great, I' ll report as soon as I can. Thank you very much!!

Hi all, I' m a newbie in troubleshooting but I'd like to solve a quarter fan spin issue on a 820-5509-A board. Where should I start to solve this problem? Any suggestion is useful! Thank you!

Hi everyone! I' m a newbie in motherboard repairs, I joined this forum to have some suggestions in my first repairs. I'm from Rome, Italy I'm 45 and I've been always a Mac lover and big Commodore Amiga user in childhood. I like to repair everything is interesting for me and I think I can learn a lot from you guys here.

Systems had so far:

- Intellivision
- MSX machines
- Commodore Amiga 500, 600, 1200
- iMac late 2012
- Mac mini 2012
- Mac Pro 2008
- MacBook Air 2020 M1

Hope to have fun with you guys, cheers!...