6" eartLCD won't turn on anymore!

hi
i need some help with my earthLCD touchscreen. i'v gotten the 6" TFT with vga controller and touch kit. it really worked nicley for about half a year now and i was very pleased with it.

i always had troubles to get my touchscreen to work. as i wanted to try again last saturday i took it out of my car, took it inside the house, attached it to the 12V AC-DC power supply i always used and the screen would not turn on anymore. only when i plug it in i see the backlight flash once and that's it. after that i can't turn it on, no matter how long i press the power button! i thaught my power supply might be bad so i went back to my car and plugged it back in, but same thing! it doesn't come on anymore..

does anybody have any idea what i might have done wrong? is my screen broken?

i appreciate any help (since earthLCD is providing an absolutely lousy support (i always have to fight for replays to my mails) )

regards
pascal

You may be blown a pico fuse or something else when either unhooking it from the car or hooking it up in the house. Can you see anything that appears blown out on the board?

nop .. can't find anything that looks blown out.. checked it once again.. i have also checked the fuses i found but they are all ok..

as soon as i unplug the board and then plug it back in, i see the light coming on for half a second again... strange..

It could be a pico fuse, which is a surface-mount fuse. Very very small and hard to determine visually if it's blown. Best bet is to do a contuniuty check with a meter, if you can. Also, make sure nothing's shorting out....touching the board where it's not supposed to.... could be another chip, too..... good luck.

Sounds like an inverter problem

today is a lucky day... i checked all the fuses and i didn't find a broken one.
i also thaught it must be the inverter since i see the backlight light up shortly. i didn't touch the board of my touchscreen, so i guess my chips and stuff should be fin, BUT i messed around with one of the two pairs of cable that go from the inverter to the screen, because the black cable of this pair acutally had some tention on it, as i figured out...

now, i just disconnected this pair from the inverter and my display is back to live.. of course not as bright anymore, but better than nothing, and better than my crt solution as well ;-)

can anybody explain to me what is wrong with my backlight? is the inverter broken or are there some connectors inside my tft where i just need to firmly connect the cable again and it works? or is maybe my backlight broken?

i appreciate your helping... i am quite a newbie (as far as writing is concerned) and i already LOVE this board!
THANK YOU so far!

what i mentionned before, that the wire had some tention on it was not true. i just found out that it was acutally the one still working that had tention on it.. so never mind.. .

meanwhile i have measured the resistance across the two pins of both connectors that connect the display to the inverter ... on the display side there is no connection between these two pins on either of the two connectors, so obvousley there is not short or anything like that..

i should i try to switch ports on my inverter, so i can figure out wether it is the lamp or the inverter that's bad, or do i risk to burn the other lamp / inverter when doing so?

what would you suggest..

btw.. still got no answer from eartLCD!

I doubt the tube being bad would couse this - sounds like the inverter is shot

okay, so as soon as i get home, i'll just try to use the the half of my inverter on the other tube and then i see if it turns on or not.

btw. sent my newest ideas to earthLCD today and got an answer! but the content of it is not really what i wanted ...
"Without you having replacement parts,,,,the only thing you can do is send it back" well... i won't have any audio in my car for a month or even more (who knows how long this might take, if it takes a week to answer an email (and this was the best case.. )

hope it is the inverter.. this way i can just ask them to send me a new one or maybe just order a new one myself and connect it..

we'll see..

I could now locate the problem. I figured it is a malicious connection in the black cable that goes to the lower tube. I have figured out, that, when I move the part where the round cable meets the flat cable (inside the red circle on the picture below), I get rid of some noise on the screen and when I have a totally clear picture and constant backlight I can even let the second tube be plugged in, so I get the same bright picture I used to have earlier. As soon as the noise comes back in the picture the backlight turns off again. it won’t turn off as long as I only have one tube connected; the one on top being perfect and the one on the bottom having this malicious contact. I have then tried to only move the ends of the cable and I have figured out that nothing changes, if I only move the end, where the cable is attached to the tube or the other end where the connector is attached to. So I then tried to move only the middle where the round cable is attached to the flat that goes to the tube… and there I had big differences.. so I am quite sure that the problem must be there..



Btw. I have also chaned the ports on the inverter so the top one connects to the earlier bottom part of the inverter and vice versa, so I can say for sure that it is not the inverter that went bad.. and since I can get rid of all the effects by just moving that one black cable, it can’t be the tube either, so it’s just the cable connection..



Here you can see a picture of the part I am talking about.. the black junction inside the red circle is the malicious connection I mentioned before:
http://www.psuter.ch/invcbl.jpg

i have sent this to earth and they replied within some minutes!!!!! .. i asked them to send me a new unit and charge a deposit to my visa.. maybe they saw "charge visa" and responded .. ;-)

thanks for all your help.
pascal