Switch - overheating

Some friends of mine had the worst possible nightmare. A switch that kept overheating during school holidays, and thus kids going nuts. But the strange thing, is that the controllers wouldn’t charge / be detected when connected as well. Interesting!

They asked if I could take a look, and if could do something about it.

The Switch itself looked really clean. I wouldn’t see why it would be overheating. Practically no dust. But I did notice the fan didn’t run.

As said, after cleaning all the old thermal paste, and booting it up, I noticed that the fan just didn’t start spinning. The fan itself was fine, but there was a short on the line, where the fan is connected.I decided to inject some voltage, to see if I could trace where the issue was coming from.

It didn’t take long to see where the issue was coming from - the thermal cam gave it away quickly:

There’s a little diode to protect from back-EMF from the fan. That diode was shorted. And would you know, that same circuit is providing the 5V to charge the JoyCons.

Simply replacing this little diode, brought the Switch back to a healthy condition :-)

Happy repairing! - 73 de ON8AD