IMac - new SSD/RAM but have black screen and no OS

[kneeoil]

(iMac Late 2013 - 21.5" 2638) I have had a lengthy repair starting with trying to upgrade to a SSD and upgrade the RAM; I purchased both from iFixit.com. Unit starts up; i.e. I can hear the fan spinning and after several seconds I hear a start-up chime, but the screen stays black; no apple logo. I have checked and the LED lights on the motherboard are all lit (except for the top / 4th one). I think this is happening because there's no OS installed on the new SSD, but I don't think I can do the internet OS install as I have a wireless keyboard / mouse that aren't paired to the computer yet which I think you use to initiate the OS download process. Thanks for any guidance!

 

[Cory Cooper]

Hello and welcome.

Sounds to me like there may be something may have not been reconnected properly during the repair - possibly the display power and/or data cable. You would get an image on the display without having macOS installed.

• Have you checked and double-checked all of the internal connections?
• Do the fans spin up to maximum RPMs?
• Do you happen to have an external display you can connect and test for an image?

C

 

[kneeoil]

Cory - thank you. I do not have an external monitor but I did check the cables / connections. Fan does end up spinning to max pretty quickly. I can try to find some new LCD cables and see if that is the issue.

 

[Nurgle2024]

if there is no Os installed you would still get the 'Floppy disk' icon with the question mark asking for a system disk, may be a video ram problem.

 

[dchyde]

Have you put a system disc in the disc drive and booted holding the 'C' key down. You need to get a system that the Mac can recognise so that yo can format the new SSD.