Need Help: Onkyo DV-SP502 DVD/CD Player Won't Power On

I recently inherited a (what appears to be) minty Onkyo DV-SP502 DVD/CD player. I picked it up because it has a good DAC and can play SACDs. I hope to use it as the CD transport for my hodgepodge HIFI system.

The problem that I am facing is that the player will not power on when I plug it in. It will not turn on or go into standby mode. The person who gave it to me kept it in good condition, clean setting, and reported that it had previously worked without any problems.

My guess is that something is wrong with the power supply, perhaps? But the fuse appears to be intact and I do not have the equipment to test if a current is passing through the board. From the included pictures, does anyone have any ideas on what could be going on or what I could try to trouble shoot?

If it helps, the instruction manual does state the this player has some sort of specialized power cord that is designed to work specifically with this player—and that other power cords shouldn’t be used with it. I am not able to identify at this moment if the included power cord is the stock cable.

If you need further pictures or info, let me know. I’ll try to be responsive.

Thanks for the help!

(player interior)

(power supply board)

(power supply board)

(power supply board)

(power supply board)

(power supply board)

(disk drive)

(DAC board)

(player I/O)