Odd Problem with Late 2013 iMac after HD Replacement - Help!
I have been servicing Macs since 1995 and I can't figure this one out.
A 512gb hard drive in a 21.5 Late 2013 iMac died. I replaced it with an SSD of the same size.
Now when it boots, the Apple Logo and the progress bar are missing - just a black screen - but after a minute or so, the login screen shows up. I can then log in and the machine is normal.
If I restart, it chimes, I get a black screen with no apple logo or progress bar, and then back to the login screen.
If I start in recovery mode, no apple logo, no progress bar, but after a minute I have the recovery mode screen. Same with booting with the option key down / and in Safe mode.
I've tried zapping PRAM, resetting SMC, tried with Sierra/High Sierra/Catalina no difference. I even tried another SSD thinking the power difference might be an issue. No difference.
The computer works fine after booting, it's just the initial startup no matter what way you start the machine up is missing the standard Apple logo and progress bar. Any help would be greatly appreciated.
iMac Line (2012 and Later)