Chosen Solution
After having replaced the broken screen on my ASUS Zenfone 2 Z00D, and reassembled it - the SIM tray appears to not be working. The same SIM that was lodging in it before the repair operation is not being recognized by the device. I tried everything:
detaching/reattaching the antenna connector on the bottom right daughterboard and on the mainboard; same with the connectors above and below the battery (the ones from the microSD and the SIM - they belong to the same part) Literally everything works except that part, even the microSD. What could be the problem?
Sounds like the SIM tray flex got damaged either during the repair, or prior to it (assuming it is plugged in properly). The SIM tray flex, which also has your SD slot on it, likely needs to be replaced. Note that this is probably adhered to the battery as shown this photo. It might be safer to look for a battery replacement that has the SIM tray flex if you are going to attempt self-repair.
