efcmandan

Hi all

I have a problem with this screen (click) that hopefully you'll be able to advise on.

I bought the screen a while back, and have been busy fabricating the surround into the console in the car. I'm happy with that now, all primed and sprayed and ready to roll. So, last night I start to put all the components of the screen back together, as I had removed the touchscreen overlay, the screen itself, and all three PCB's from the housing.

I disconnected the speaker, as I won't be using it, and 'roughly' put everything back as it should be. Connected up the power, and found that the screen will only stay on for about one second.

I've connected my laptop to the VGA, and when I switch the output to 'external' the Windows desktop image appears on the 7" tft but only for about 1 second, before going off again. There also appears to be some strange lines across the screen

Because i've taken it all apart, I've voided the warranty, so I can't send it back.

I'm sure it can't be knackered, so can anyone possibly suggest what the problem might be? Do you think, because it's not all back together properly and I'm holding it upside down with PCB's dangling, that maybe something is shorting? Or there's an earth problem? Or maybe because I disconnected the speaker?

I'm gutted, mainly because of the expense, but also because it all needs to be working before May 19th!

Any help appreciated.

MP3Car.com

 

tim123

Check that the screws that hold it together aren't used as a ground connection for something.

Could be that because the screws aren't in, one boards ground connection isn't passed to another.. obviously check all your connections.. make sure the power button isnt' being pressed accidentely etc..

Just a thought,

Tim.

efcmandan

Hi Tim

well, the screws that go from the rear to the front are just through plastic and have nothing connected to them, so I don't think they are used for grounding.

BUT, I wonder if, like you say, that grounding needs to be passed from one board to the other, and because they're all dangling...hmm...

I'm pretty sure the power button isn't the culprit, but I'll double check all that again tonight.

Thanks for the advice.

Dan

efcmandan

Hi Folks

well, I fixed the screen

Basically, it wasn't an earthing problem.

Within the enclosure for this screen, there are three printed circuit boards (PCB); the main one, a power invertor, and the USB controller board. Now, obviously all these boards are joined together with ribbon cables and what-not. There was a three-pin connector (with only two wires), that went from the invertor to the main board. When I put everything back together, I found a three-pin socket on the mainboard and plugged the three pin connector from the invertor board into the main board, into the only 3-pin connector on there. Then, the screen would only come on for about half a second before powering itself off.

So, after much multi-meterage and head scratching, we found that the screen was only getting 5v when connected in this way. Turns out that this three-pin connector actually goes into another socket on the main board which had about 8-pins(?!), when connected into there the screen gets 12v and all is well!

So, I'm a happy chappy and I'll get some pics up in the relevant sub-forum!

Hopefully if anyone has the same problem as me they'll find this thread.

Borndead

Please put up some pics if you can. I'm having similar problems with my display, but mine stays on for about a minute. It started doing it out of nowhere, without me playing with the cables, but i'd still like to verify that i have everything plugged in correctly.

MP3Car.com