[SOLVED]820-3435 trackpad not clicking & keyboard not working

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I got this 820-3435 that was a no backlight. The lcd cable was burned and there was water damage in the area. I replaced the connector and cable and now it boots up fine.

When I boot up I get taken to the Reset Password page with the three options. I can move the cursor around with no problem but when I try to click it doesn't work. I've tried using the arrow keys on the keyboard to select an option as well as turning the computer off with the power button but that didn't work either. I hit the caps lock button on the keyboard and it didn't light up.
When I click the trackpad the bottom of it has a weird click to it where it kind of pushes in like it is not screwed in even though I tried tightening the 6 screws on each side of the tpad.
I plugged a brand new keyboard in and that one didn't work as well.
I also plugged in an external wired logitech mouse and the lights flashed on the mouse but it didn't work.

I do not have another trackpad or flex cable for this model to test but I can order one if needed.

Here are voltage mode measurements I got of J4800 without the keyboard plugged in

pin1 3.4v
pin2 0v
pin3 0v
pin4 0v
pin5 0v
pin6 0v
pin7 0v
pin8 0v
pin9 0v
pin10 3.32v
pin11 3.32v
pin12 3.32v
pin13 3.3v
pin14 5.1v
pin15 0
pin16 3.32v
pin17 3.32v
pin17 3.41v
pin18 3.41v
pin19 3.43v
pin20 3.43v

R4850/R4851/R4852/R4853 all measured the proper resistance but when I look in that area I see there are some probe points in the area that are slightly red.
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Staff member
firstly for it to click properly you need to tighten the t5 screw on the edge of the machine which is about 2" below the 6 screws you tighten to screw the trackpad into the machine.

and try with known trackpad!


The T5 trackpad sensitivity screw is completely missing from this board.

Update: Found the screw in a plastic baggie sent with the machine so now I have that screwed in it should work.

Once I get that fixed the click should work but that wouldn't solve the keyboard not working issue would it?

larossmann Do you have a trackpad for this model you could sell me because I have some ordered from aliexpress that will take weeks and I don't want to order one from L2 on ebay?
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