My Apple TV 4k died over the weekend. It's possible it suffered a power surge during a heavy rain storm, but it was connected to a surge protector. I tried connecting it to a different outlet with a different power cable (from another working ATV4k unit) without success. From my reading it sounds like it might be a bad power supply. Before I buy a new one, I would like to test the current power supply.
My plan is to connect the power cord and measure the VDC at the conductive posts (red circles in the picture below). If the power supply is bad, I shouldn't measure any voltage, correct?
Also your surge protector needs to be replaced. Depending on where you live and how dirty your power is, you should plan on replacing them every 2-5 years.
Tear down complete. Of course the power supply is the deepest component.
Connected the power cable and I measure 120 VAC on the pins immediately adjacent to the power jack (confirming the problem isn’t there). When I measure at the output conductive posts, I get 0 VDC.
I’ve ordered a replacement power supply off EBay. I’ll post an update once it has arrived and I test it. As Shadowfire said, it’s possible more than just the PSU was damaged.
This is not surprising given the amount of silver discoloration I could see on the chassis, power supply, and logic board (see pic below near the Ethernet jack). Looks like it was cooked pretty solidly.
Unfortunately the last step is buying a new one. If anyone would like the Apple TV for parts or as a project, PM me and I’ll send it to you.