I have a Sony KDL-46EX720 that turns on, plays sound, but there is no backlight and I hear a constant clicking from the TCON board. It goes away if I disconnect the LVDS from the TCON. Thoughts?

If you remove the back and look in the various openings to the panel can you see normal backlights?

6 red flashes- backlight issue, bad main board, or power board or inverter boards- check standby volts on power board. "backlight on" volts should be 3-5v from main logic board then 24v to inverter


Have this from a youtube link find BUT
Better is to look first also on bad leaking or bulged capacitors thats better to replace in the bad components to get a repair because active components died on bad capacitors but after a while because on the build-in protection circuit by faults like deformed or leaking capacitors and even several fuse resistors then after replace a complete board again after a while you will may be get the same kind of problems again, take If you find some or much bad capacitors replacements 10 volts dc higher . begin with control on the power supply first of all.



Sony Bravia TV kdl red blinking led light error codes solutions Sony KDL 40XBR4 KDL 40XBR5 KDL 46XBR4 KDL 46XBR5 Service Manual

Refer to Sony KDL 55EX500 Troubleshooting Manual Protection Mode Symptom...
5X Blink - TCON & HFR Failure
The 5X blink protection mode indicates a communications error between the TCON/HFR board and the MT5388 microprocessor on the A-Board.
First replace the TCON/HFR Board if the 5X protection mode blink pattern occurs. If the TCON/HFR Board does not repair the problem then replace the A-Board.

see schematics in Sony KDL 55EX500 Troubleshooting Manual Page 23

The tcon bard or the LCD panel is faulty. Can confirm by replacing the TCON board.
If you wish to get some details; check the site linked here. Pull up older posts
http://electro-medical.blogspot.com/

Hi there , this may or may not help but i have a sony model KLV 46X200A i had the same fault only green led going and you could hear the sound of a relay click nothing more , to cut a long story short the TCON board was faulty , as it was hard to get hold of a replacement , i found that a very small fuse on this board had gone open so replace this fuse with 1 from a laptop backlight board , the tv now works fine , i hope this helps .

Check and replace its back-light inverter board. If you wish to get some details, check the site linked here. Pull up older posts. Check the site in 'Mosaic' view. It will make search easy. http://electronicshelponline.blogspot.com/

by audio speakers i assume you mean speakers that you plug INTO the tv, some tv's if you plug in speakers they play instantly but some tv's you might have to go under the menu ON the tv so just bring up menu, click on audio, and it should say some where to swith to external speakers then while with speakers pluged in select external speaker (or whatever your tv might say) and i hope that solves your problem, thank you, jamie.

What does it do if you unhook the flat cables going from the tcon to the panel, does the blinking go away and do you have sound then?

Could be the power board or main board defective, but I suggest you do firmware update first. Go to http://esupport.sony.com/US/perl/swu-list.pl?mdl=KDL42V4100&LOC=3#div_pos_30 download the software.

Remove the LVDS cable, the one going to the input of the tcon board and see if it goes dark, if it does the Tcon board has failed