Surface Laptop 4 no USB (Intel i5)

[Vanillaboard]

Hello,
After my Surface Laptop 4 was rejected by Microsoft repair due to an alleged water damage. As a result, I've decided to tackle the issue myself. Unfortunately, after a use involving a self-soldered USB board, the USB port (not USB-C, which still works) is no longer functioning.
Now, I suspect that a short circuit may have damaged something on the motherboard. I've checked for any visible damage according to the schematics but couldn't find any. So, I decided to check if there's any voltage on the Vbus. Sadly, it's reading 0V. I've traced the supply and came across the NO-MSPN-00312 controller. Initially, it has a 3.3V input voltage, but there's no output voltage anywhere. Now, my question is: could a faulty ic be the cause? The IC has a 'SENS' circuit as well; what is this for? Could anyone provide a hint as to its purpose?

i also attachted PDF Shematics .

[MOD EDIT] Link to schematic - https://www.badcaps.net/forum/troubl...ntel-schematic

Reminder: rules and organization of this section - https://www.badcaps.net/forum/troubl...f-this-section

Maybe someone can help me here, would be awesome

Thanks

[mon2]

If there is no short at the output and you have the input at +5v then the usb load switch at u4503 is defective. Review it but it should be replaced. You will need proper tools + flux + some experience on another board before attempting this replacement. Or ask your local phone repair shop that can handle board level repairs.

[Ken123]

Im not an expert but where you had 0v, did you check for short there?

[Vanillaboard]

Im not an expert but where you had 0v, did you check for short there?

Hello,

on USB VBUS i have 0 Volts. so after the ic i havent any Voltage. Only on IC input.
No short here. :/

have to reverse my measurments.

I have this chip: NCP380HMUAJAATBG
https://www.mouser.at/datasheet/2/30..._D-2317053.pdf
Its U4503 on Shematics.

On Input PIN 5 i Have 5Volts.
Output PIN 1 is 0V (No short to Ground),
On En PIN 4 i have 1.8V
on SIDE GRound Pin 5 I also have GND
and on Flag PIN 3 i Have 3.3V
SO i Have no Output.
The 3.3V should say me that there must be a problem on putput right?

[Vanillaboard]

short to ground.
Maybe this s the issue? i desoldered t but still have 3.3V on FLag Pin.
The short on output is not present Anymore.
The weird thing is that after i turn laptop on for check i have short again.

[mon2]

If there is no short at the output and you have the input at +5v then the usb load switch at u4503 is defective. Review it but it should be replaced. You will need proper tools + flux + some experience on another board before attempting this replacement. Or ask your local phone repair shop that can handle board level repairs.

[Vanillaboard]

If there is no short at the output and you have the input at +5v then the usb load switch at u4503 is defective. Review it but it should be replaced. You will need proper tools + flux + some experience on another board before attempting this replacement. Or ask your local phone repair shop that can handle board level repairs.

Hello,

i did have short. I was wrong in the first measurment.
So i desoldered the Kapasitors first but no solve. after i disoldered u4503 and short is gone.
as you said i need replace this.

Thanks for all