Nintendo Switch - 0.00A - no shorts - diagnostic help needed

I received a defective switch which does not turn on and does not show any loading activities. When connection to USB I get an 0.00A on my device.

I have not found any shorts.

I measured D+/D- (w/o battery connected and they show 0.840)

Now I have no idea how I can further diagnose in a good way to find out why no power is going into the switch.

Any help is appreciated.

Above the test point 6 is a fuse (light green marking). I would check for continuity.

Thanks @Calvin - Fuse is also checked and have continuity

What are your voltages at the m92t36?
The voltage at pin 28 (5 V*) depends on the input voltage from the powersupply.

I must correct myself - with the start of the diagnose of the MT92T36 is seems that PIN 18 is shorted - as well as the IC next to it.

Assume this indicates a defect MT92 or bad soldering (not sure was was done with the switch before)

Screenshot 2021-06-12 140135

I mean PIN 9… as shown oin the pic

If the usb c port doesn t show any disarranged contacts inside, I would remove the fuse temporary and check on which side the short belongs.

Thanks Calvin for getting support in the diagnostic which helps a lot - much appreciate your work.
Before taking off the fuse (which honestly I have not understood what can I see once fuse is off) - I inspected USB-C connector a little bit depeer. Inside I could not see any problems, but checking the soldering of the PINs I have seen that 3 of them are not soldered on correctly. So I guess someone tried to replace the USC port before.

Once soldered them on correctly powering up was working - but unfortunatly switch is still not fully working. Backlight, Touch is working but nothing on the LCD screen. It looks like that one PIN of ther FPC Display Port connector is broken - so this probably needs the be replaced as well :frowning:

Haven’t done this before - so hopefully I can manage this…

The fuse devide the power supply line in two parts: the usb c side and the m92t36 side. If the fuse is off, the shorting component should be only on one of the both sides. In your case the usb c side would be stayed shorted and the other side would be tested without shorts. → The short is at the usb c port.

From my point of view three loose pins can not short VBUS and GND. I would first check if all pins at the visible and hidden row are making good contact and do not short against each other.

If it all seems ok I would test if the Switch displays on a tv.