Techwood 32722HD (17MB15E-7?) parts of image negative

[g_attrill]

Hiya, I have picked up a Techwood 32" LCD.  The fault is that the picture is washed out/negative at what seems to be the darkest parts of the image.  Before I start taking it to bits, has anybody seen this fault and can suggest what the fix is?   The main board has 17MB15E-7 printed on it, I think this is the Vestel chassis model number.

(click for large pic)

Also, I can't get it into the service menu, the Menu+4725 doesn't seem to work on this TV, any ideas on how to get in?

Thanks!


edit: An evening of googling has brought up these two useful posts, I will look into the cabling:
http://forum.eserviceinfo.com/viewtopic.php?p=120855
http://forum.eserviceinfo.com/viewtopic.php?p=120861

[chrissie jones]

T.con. timing control board

[gianpaolo]

Ciao, controlla il Cavo Lvds collegamento tra Main e T-Con,  puliscilo bene, poi rinseriscilo. :ciao:

[In_Focus]

To obtain the service menu the TV must not be in DTV mode, it will only work on an analogue channel or AV mode.

When you've got it in service mode look in the picture settings and turn LVDS mode "off" if the LCD panel is a Samsung LTA320WTL-05.

[g_attrill]

Ok, mark this one as a success!  

Firstly I removed cleaned and reseated the plastic ribbon cables between the screen and the t-con board, and then removed what I assume is the LVDS cable for testing.  The connection in the black/white wire seemed dodgy so I cut it to test which end the problem was.   It then seemed to test fine so I soldered it back together, cleaned the edge connector (t-con side), replaced it and the picture is fine.  I assume it was dodgy at some point and fiddling around fixed it, hopefully it will be ok for the rest of the life of the TV but I know roughly where to go should it happen again.

Many thanks for the suggestions, I have a nice TV for the kitchen now!


(large pic)

In_Focus: The panel was different, LTA320WT-L13 I think, also I did manage to get into the service menu but it was different to the menu in the Technika I have, which has the picture settings sub-menu, this one has a very limited set with none of the detailed options.

[chrissie jones]

good testing.

[blueskysea]

Sometimes, if the LVDS cable between the LCD panel and the main board is not very good , it would cause the TV screen display abnormal. I bought a 15 inch tv for my kitchen and it works well for a long time.The price of the 15 inch flat screen tv is 90USD.

[sinclairtv]

Jeez I thought Chrissie had returned

[Turnip]

Hi Sinclair,

So true, we miss his 'down to earth' expertise with back screws - Chris.