Hannspree HF255

[rokrep69]

Hi,
Working on a Hannspree HF255. It powers on with a white screen, then goes dark after a few seconds. Capacitor look ok but have not tested them. Looking for any ideas...

Dan

[budm]

Re: Hannspree HF255

Pictures of the boards? It may have gone into standby mode if it is not hooked up to running PC. White screen may mean the T-CON board is not getting the voltage to it or it has blown fuse on the T-CON.

[rokrep69]

Re: Hannspree HF255

Hi,
Here are 2 pics of the boards. Pardon the low grade, shakey cell phone pics, my rechargeable batteries for the "good" camera have died.

http://www.dtgl.us/pics/1.jpg

http://www.dtgl.us/pics/2.jpg

The monitor failed on me about a year and a half ago. I had bought the thing new and really liked it.

Dan

[budm]

Re: Hannspree HF255

There should be the T-CON at the LCD panel assembly, it may look like a big long board that has wires going to the main board: for example
http://s807.photobucket.com/user/bud...ml?sort=3&o=26
Or it can be a replaceable T-CON board like this under the metal shield.
http://s807.photobucket.com/user/bud...ml?sort=3&o=11

[rokrep69]

Re: Hannspree HF255

Here are the additional pics. I now know what a T-con is :P

T-Con (L & R)

http://www.dtgl.us/pics/3.jpg

http://www.dtgl.us/pics/4.jpg

Serial numbers

http://www.dtgl.us/pics/5.jpg

http://www.dtgl.us/pics/6.jpg

Thanks,
Dan

Additional Fuse pic

http://www.dtgl.us/pics/7.jpg

I'm assuming this is the fuse. How can I test it? Continuity work?

[budm]

Re: Hannspree HF255

Set the meter to the lowest Ohm scale, monitor is unplugged, it should be less than 1 Ohm.

[rokrep69]

Re: Hannspree HF255

Meter set @ 200 ohms (lowest) and it reads 00.2 across the fuse

[budm]

Re: Hannspree HF255

OK, the fuse is good, so now we need to find out if has either 5V or 12V DC on the fuse terminal. Measure it with monitor on and connected to the running PC, Black probe on the chassis, red probe on either ends of the fuse.

[rokrep69]

Re: Hannspree HF255

It measures about 4.6v

[budm]

Re: Hannspree HF255

OK, this is enough to run the T-CON. Not much you can do at this point, there are other voltage regulators and switching power supplies (you can see the black round inductor) on the T-CON that may be not functioning, I do not have much luck fixing the T-CON board myself, so may be some one else can chime in.

[rokrep69]

Re: Hannspree HF255

Thank you for your help. I'll wait on any advice from others, before scraping this thing. I assume replacement T-Con boards are hard to come by?

[budm]

Re: Hannspree HF255

You will have to replace the whole panel.

[rokrep69]

Re: Hannspree HF255

I'm not surprised. I'm done with cheap chinese crap.