plugging video cable in temporarily shorts mother board

[deathtokoalas]

so, i've been working on my laptop for a little while. i took it apart, and thought i had bricked it by shorting out the board. but, it does not seem as though that is actually the case - the short seems to be connected to the video out. i'm just not sure exactly what the following behaviour indicates.

this is what happens...

1) when i  plug in the laptop with the video cable disconnected from the board, i get power around the led. keep in mind that the thing is disassembled, so i can't actually turn it on. but, the light is there, indicating that the circuit is completing.

2) when i try and plug the video cable in, the light stops, indicating that the circuit is no longer completing.

therefore, the short is in the video cable. but, what happens next is making me question whether it's in the cable or on contact.

3) when i try and plug it back in immediately after i unplug the video cable, the circuit does not immediately complete. i have to reseat the jack, sometimes repeatedly. but, it always come back, eventually. of course, the circuit stops completing immediately after i plug the video back in, and i get the same problem again.

why is this happening? is the motherboard shutting itself off to protect itself? if so, does that indicate the problem is in the connection rather than in the cable? or does that just sound like expected behaviour from a bad cable?

[deathtokoalas]

another idea...

i've tested the power jack with a multimeter, but it only goes to 6.5V. could the video be attempting to draw too much power from a broken dc jack, and shutting the entire board down? could it just be a jack, after all? could that then be why i have to reseat it multiple times?

[sandytechy20]

@deathtokoalas

Welcome to the HP Forums    

I saw your post on broken dc jack.

This seems to a hardware issue.

I request you to contact HP Phone support for further assistance on this.

Cheers.