XBox Series Controller - Component ID

[sweep]

Hi, I'm trying to fault find and repair an XBox Series controller. I've "decided"* that the transistor at location Q3 on the main board is at fault (not turning on) and would like to try and replace it. My understanding is that it is a switching component that activates when the power button is pressed - so it is responsible for turning the controller on and off. It has the marking WJ3 and a 10.

Two questions - is my basic understanding above correct? What specification / code replacement do I replace it with?
I've been looking for SOT23 MOSFETs, but would just like some guidance, please.

* when I plug the board in to USBC nothing happens. When I place my finger on it, the LED lights up... so I suspect my finger is completing the circuit. This doesn't work when pushing down with a plastic spudger, so don't think it is a dry joint.

 

[73's de Edd]

SIR SWEEP . . . . .

Neither WJ3--- nor ---1o are researching out as being viable identifier codes for Q3.
So o o o o o o o o o lets just take DC metering and see what is to be found .
I am more inclined for Q3 to be a common bipolar transistor. . . . . . probably NPN.
Look at your provided photo, that would have its top left terminal as being BASE which takes a foil trace path downward and passes thru R10 and branches off to ground plane thru R13 and their junction passes on down to ?, where Q3 activation voltage is to be received.
Next, see the bottom terminal as EMITTER that connects directly into ground plane.
Lastly see the right center terminal as being COLLECTOR which tapers off down to the right via a foil path.

Lets see what type of semi that unit is, by powering up and STABBING! meter - probe to EMITTER and use meter + probe to see what level and polarity of voltage is on its COLLECTOR tab.
I'm wanting to suspect a + polarity on the COLLECTOR and U tell us that level.
Then move same + probe to see if any voltage, with its polarity, is on BASE tab ?
There, I'm wanting to suspect no voltage presence.
Next , have someone turn on the power button to see if any voltage then appears at the BASE as you are monitoring it..
If nothing happens, on that turn on attempt, seems like you should be tracking down that BASE foil trace, to find its adjunct components connectivity and why no voltage is being there at turn on.

To check for that Q3's functionality , monitor COLLECTOR voltage again by holding + probe there.
Moisten one hands thumb and index finger tips with moderate spittle and touch between the COLLECTOR and BASE tabs to place the produced wetted conductive resistance between them.
The COLLECTOR voltage should change / shift downwards.
Plus your "LED" should then light up as before . . . . . . and if I understood your very terse explanation correctly . . . . . that active LED signifies full system operationality ?
Thaaaaassssit . . . . .

73's de Edd . . . . .


All pro athletes seem to be bilingual.
They fluently speak, both, English and profanity.
.