toshiba lcd backlight light only ?

[jjcool]

hi

i have a Toshiba 46ZV555DB set powers up and i can see the backlight lights the whole screen up ok.

fault is that the backlights are on but theres no picture or osd or anythink just backlight untill i can get lcd into normal tv analogue channels..

after some further investigation i managed to get a full picture on lcd, from trying blind with remote to switch av channels i managed to get picture to come on when tv is on normal tv av tv channels.

however soon as you switch av channels to hdmi, or scart or feeview mode, the lcd reverts back to just blank screen with backlight on, i can still hear sound on all inputs.
i have also noticed when the picture is on in the middle of screen theres thin black lines showing across mid of the screen and also there seems to be a mirror image reflected at at bottom of screen, i have attached a couple of pictures showing both faults.




has anyone come across this problem before? or any ideas what to try next.

i have tryed reflowing both main and tcon boards set still remains the same.


thankyou

[The_AntiRAM]

Try diagnosing power supply fo ripple or other issues.

Probabily the main is defective.

Check connectors especially LVDS.

[jjcool]

would you say its the main av board fault or a t-con board fault?

thanks

[The_AntiRAM]

[jjcool]

oh ok i did not know that.

everyone thought it maybe a t-con fault. so are you saying the t-con plays no part in the anologue signal, and a t-con would not cause a double image as shown in pictures? as thought everythink passing through t-con.


i have connect a 2nd tv to the scart of the lcd and picture displays ok on 2nd set connect through scart socket so thought av was ok. however im not expert. do you still think av board?

i have noticed the big chip on the main av gets red hot.

however im unsure if thats normal.

heres a couple of pic,s of the chip that gets red hot.

[The_AntiRAM]