2009 iMac

[Oldie54]

Hi all, recently had my iMac go off with a loud bang. Nothing worked. Replaced power supply and now get a healthy chime, fans run and can hear hdd chippping away but screen stays stubbornly black. Tried cmd option p an r reset for 4 chimes but no joy. Any ideas what to try next? Old power supply had black charring round the two black wires coming from the bottom of the board.
Thanks in advance.

 

[Cory Cooper]

Hello and welcome.

Sorry for the delayed response.

Sounds like the power supply definitely fried. Since it was replaced, maybe the logic board/graphics card/LCD panel were damaged as well? Does an external monitor work if connected?

C