Which components should I test to help diagnose this laptop video problem? It works with hdmi out only, after a probable short

joe7dust

Honorable
Nov 1, 2014
2
0
10,510
My buddy was attempting to replace his keyboard and said he accidentally let some metal make contact with the main board. Afterwards he can only use hdmi to his TV and the internal screen never lights up at all.

I took it apart and thoroughly tested the cables. I was hoping to find a short in the main lvds. After some testing with the multimeter and seeing that pins 3 and 9 are shorted together, I unraveled the cable hoping to find an unintended short there. The cable integrity looks good. I noticed that pins 3 and 9 are both black so I am going to assume that this normal because they are both ground.

I am now at a crossroads where I believe it to need a new LCD panel or a new motherboard. I would like to do further testing on the motherboard before ordering one of those two parts. Which components should I test specifically?

Here is a picture! https://i.imgur.com/MwTJoKR.jpg
 
I cannot help you with the problem, but
- your photo skills are way out of range. The only think I can tell is that this is some HP laptop
- if you provide exact model of the laptop, and any markings on the motherboard, someone with more knowledge might be able to help
 
I cannot help you with the problem, but
- your photo skills are way out of range. The only thing I can tell is that this is some HP laptop;
- Pins 3 and 9 are available probably on ten different places on that motherboard;
- if you provide exact model of the laptop, and any markings on the motherboard, someone with more knowledge might be able to help.
 

joe7dust

Honorable
Nov 1, 2014
2
0
10,510


Sorry the megapixels on my phone aren't that high and the focus for closeups usually sucks. https://imgur.com/a/DNYuY

I just want some general advice on where to put the multimeter probes to start testing the circuitry and components related to internal video. A schematic for 744603-001 would be nice then no Pic needed.