7 inch touchscreen now powering up

**superman19** · 02-05-2004, 11:09 AM

I bought one of the 7 inch touchscreen kits from digitalww and was very happy with it for a day, but now it won't power up. The LED on the control board won't light up either. I've checked the power supply, and it works fine. I've checked all the connections, and everything is in tight, but the screen won't power up. Any ideas?

Thanks!

**digitalww** · 02-05-2004, 11:28 AM

You guys have to be more careful with these. They very are easy to break if you're not paying attention. I broke a couple of these monitors myself so I know.

Everything has to be isolated. LCD panel has a metal frame and it can easily short something out on the VGA controller. Unplug everything from the VGA controller and test it alone to see if the LCD turn ON.

These toys are not cheap.

Armen

Originally Posted by superman19

I bought one of the 7 inch touchscreen kits from digitalww and was very happy with it for a day, but now it won't power up. The LED on the control board won't light up either. I've checked the power supply, and it works fine. I've checked all the connections, and everything is in tight, but the screen won't power up. Any ideas?

Thanks!

**burnout.no** · 02-05-2004, 11:36 AM

Originally Posted by digitalww

These toys are not cheap.

I second that!

**superman19** · 02-05-2004, 12:05 PM

any idea of how i would test each component independently if the power goes though the LCD controller?

**wi77iam** · 02-05-2004, 01:55 PM

Originally Posted by digitalww

These toys are not cheap.

Armen

They're not inexpensive, but they are cheap.

**superman19** · 02-06-2004, 07:23 PM

so does anyone know how to test each component individually? also, can someone tell me what the inverter does? thanks.

**shchua** · 02-06-2004, 10:09 PM

Originally Posted by superman19

so does anyone know how to test each component individually? also, can someone tell me what the inverter does? thanks.

I'm not sure that you can do this unless you have 2 units - you can then swop components around to see which one is bad. My suggestion is to test the screen without the touch panel. Lay out all the components (LCD panel, controller board, inverter) on a flat non-conductive surface, making sure none of the components are touching each other. It may a bit hard to do with all the interconnecting cables connected but if there's a need to place one component under another because of cable length, make sure you insulate them with a piece of cardboard or something similar. Double check all flex cable connections and ensure that the flex cable is seated firmly in the connector. My Lilliput refused to power up when the flex cable from the controller board to the front panel board was not inserted fully into the connector. Good luck !

The inverter in the screen takes low voltage DC (12V usually) and converts it into the high voltage needed by the backlight (usually a cold cathode flourescent lamp). Keep your fingers away from the inverter when it is operating. The output can give you a nasty shock if you are not careful.

**superman19** · 02-06-2004, 10:52 PM

thanks for the reply. just to make sure, even if the inverter and LCD were not connected, the LED on the controller board should light up when power is on it, right?

**shchua** · 02-06-2004, 11:29 PM

Originally Posted by superman19

thanks for the reply. just to make sure, even if the inverter and LCD were not connected, the LED on the controller board should light up when power is on it, right?

The controller board should power up without connecting the inverter, but I am not sure if it will without the LCD - it normally should but perhaps someone with actual experience can help here.

**superman19** · 02-10-2004, 10:49 AM

does anyone know how much the VGA controller board and/or inverter board for the 7 inch touchscreen cost? I've been trying to contact digitalww for a couple of days now, but can't get through. thanks.