iMac 27” mid 2011 EMC2429 won’t turn on

I got an Imac 27” mid 2011 EMC2429 which was not turning on. No chime, no fan working, Nothung.

First I thought it is PSU. I tried my PSU on another Imac it works fine. On my Imac I tried another working PSU same result not turning on.

Then I have noticed that when I plug it in, Led 1 on motherboard blinks for a second. Anybody could help me what can be broken, How to fix it?