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Shorted USB Power to data while probing

I was a bit stupid. I had a working dell 5320 Motherboard and wanted to test the USB C Voltage. So I put my Multimeter on the power pins, but by accident I shorted the 19v power pin to either the rx pin or the usb 2 lines. When I then plugged it in the led was blinking but there was no fan spinning and no screen output. After replugging everathing the whole motherboard is dead and it shows no sign of life, but I dont see any sign of burnt components

I dont know what to do. Is it worth trying to fix or is a cpu/ram damage possible?

I have a multimeter and can solder but I dont have a big knowledge on how to search for Problems.

I attached a photo, the selected pin is the power pin and I shorted either pin T8 to T9 or T9 to T10

Block Image

and here is a link to a board view File

https://thetechstall.com/dell-latitud-53...

One thing changed: I only get 5v on the usb c port now, not the 19v from before

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Hi @imnotanexpert

I could understand it happening more if you accidentally shorted out between pin A4 (VBUS) and A5 (CC1) or B4 (VBUS) and B5 (CC2) as this would have affected the power delivery controller IC (U7201) which controls the voltage options of the USB-C port.

I don't have the boardview file, but here's the schematic that may help.

Go to p.72 (of 106) to see the connections for the PD controller.

Hopefully a start ;-)

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Thanks for your answer! Because I didnt have the 18v from before I already assumed that something with the PD Controler would be off, so I ordered a new on (they are pretty cheap from china). Do you know how to test (not assume) the U7201 is dead? I couldnt find something online

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@imnotanexpert

Here's the IC datasheet that may help.

On p.20 it shows how it functions so maybe check if the relevant supply voltages are on the IC (see p.72 in the schematic).

Bit hard if you can't access the pins on the IC so check on the nearest component that connects to that pin

For example check if there's voltage on C7202 i.e +3D3V_VDD_PIC_PD etc. If it's not there you may have to trace back that supply in the schematic to find out where it comes from and why it isn't there at the IC

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