Xbox One S not turning on with functioning power supply and MOSFETs

I'm replying to this thread with the final answer as to why this Xbox One died.

It was a mosfet on the motherboard. When I took the fan and heatsink off to change the thermal paste (btw Microsoft, why the horrible thermal paste application??) I noticed one of the mosfets on the right hand side of the board looked a little off. Plugging
in the console and it started throwing a small amount of smoke. Replaced the mosfet with a fresh 20A 30V n-channel Mosfet (Toshiba brand if you can help it, as these are the OEM mosfet manufacturers), it worked great, fires up every time. Not sure why exactly
it failed, but if you do a little digging these mosfets are infamous for failing, even on the newer Xbox One S, and are responsible for many no power/turns on then off issues.

The mosfet I replaced was Q9D1. Luckily the near-by resistor (R9D2) and fuse (C92D) are fine. However, if any Internet historians with this same issue find this thread, be sure to check those for continuity.

Mosfets Q9D3, Q9D5, Q9E1, and Q9E3 are the other mosfets that have been known to fail, all along the same right hand side of the motherboard, right next to the CPU socket.

Hey there!

Sorry to hear you are running into these issues with the Xbox One console. When you power on the console, does the light turn on and stay on with no display, turn on and then turn back off, or does the light not turn on at all?

If this is the case then we will need to troubleshoot your consoles power supply. Go ahead and click on the following link for the Xbox One Power Solutions Troubleshooter.

Xbox One S or Xbox One X Power Solutions

Xbox One Power Supply Solution

Please let us know if this has helped!

Are you sure it´s not the power button?

Sounds like it´s stuck.

The power supply can´t turn your xbox on, it just turns it off if it overheat and such.

Thanks, it seems none of these issues are causing this unexpected "turn off" for my xbox one s.

Could it be due to a faulty internal power supply? And would it be fine if power supply be changed?

How to confirm if this is due to faulty power supply?

Looking for advise please.

Thanks,

Sameer Gupta

Your Xbox One console may unexpectedly turn off under the following circumstances:

The console is too hot.

There's a problem with the power supply.

Reset your internal power supply

The Xbox One S and Xbox One X have an internal power supply that works in all regions worldwide. If your console won't turn on, it may simply need a power reset. Often, power issues are due to the power supply resetting after a power surge.

To reset the internal power supply, follow these steps:

Unplug the power cord from the console.

Wait 10 seconds.

Plug the cord back into the console, and then press the Xbox button on the front of the console.

or perhaps your power supply is clogged and overheating...

Xbox One Power Brick (Day One Edition) Disassembly