820-2530 No image

[tlough75]

Ok so I have an 820-2530 that originally had no power and PP3V42 and PPBUS were .08 and no Magsafe light. Found pad under pin 5 of U6690 was corroded away so I placed a temporary solder bridge to chip and trace, now have chime and backlight but no image.

 

[tlough75]

Ok, so after some tinkering, unplugging things, plugging in things it seems I was able to at least figure out why I am not seeing an image but have not found a solution. after pulling the board, the board booted to ? folder, so I plugged in everything and powered it on, NO ? FOLDER! SO I unplugged everything, ? Folder came back. Started plugging stuff back in and testing and the culprit is something to do with the webcam connection. I confirmed with two other LCD panels and sure enough, every time I plugged in the camera cable, no more ? folder. Removed it and again, ? would show up. So my next problem is trying to figure out why the heck this connection causes the computer to not boot.

 

[2informaticos]

Compare diode mode readings on camera connector w/ and w/o cable.
Pay atention to R5270/71 and respective traces.

 

[tlough75]

Ok, diode mode readings on pins 18 & 19 are:

Pin 18: .577 w/o camera and .488 w/camera
Pin 19: .577 w/o camera and .539 w/camera

 

[2informaticos]

There is a big difference with camera connected.
Check what happens with voltage levels.