40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

It is Samsung LCD, so it uses U-shape CCFL
http://backlightweb.co.uk/images/lar...ture%20007.jpg

So each group of two pins (going to transformer secondary) is one bulb connection; that is where you should test.

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

heres what I got (see photo)

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

Seems OK. Looks to use a design where the middle of the panel is driven using a smaller transformer, odd design. I'd look elsewhere on the inverter, can we have close up pic around each transformer?

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

more photos

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

OK, looking at pic:
https://www.badcaps.net/forum/attach...9&d=1359332628

D101 is one diode for the error feed back.
There will be one other diode for each transformer.

Check the single lone pin for a voltage on each diode.

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

I found the diodes for the left and right transformers but couldn't find the one for the middle one.

Both D101 and D103 measure at 3.63V when the backlights come on and 0V when off then itll increase by 0.04V with each cycle.

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

3.6V is too high (will cause shutdown... normal working voltage 1~2V), so measure each of the two pins adjacent, and we will find which bulb or transformer is causing the problem. (Use volts AC.)

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

So AC voltage, black probe on right pin and red on the left pin?

[budm]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

Service manual:
http://elektrotanya.com/?q=showresul...oria=&kat2=all

You may want to look at shopjimmy for the replacement Inverter board.

[budm]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

I hope it is not the lamp.

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

Ebay is selling a bunch of these inverter boards for only about $12 including shipping, pretty cheap.

Even though the lamps are able to turn on prefectly, is it possible for it to still be bad?

I measured both diodes and they give me 9.5VAC

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

I'd just go for the board at $12. It's pretty unusual for the bulbs to fail without showing obvious signs (pink colour/flickering/dimmer than the rest, etc.)

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

I had already made the order. Just wanna see whats causing this problem.

[budm]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

Well, please keep us up to date, that is very cheap for SONY parts.

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

That is why I like some newer TVs for parts. More people are collecting spare parts from cracked screen TVs (mostly damaged in shipping) now so the prices fall. I just started selling parts for a 42" Samsung plasma, 2011 model, which had a Wii controller hit it. Each board now only sells for about £5 each, because there's a surplus of them in the market. This is good for buyers, bad for sellers -- but I'm mostly a buyer so it's good overall. And since most TVs get damaged in shipping the parts are practically new.

[tieny]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

I always have trouble selling inverter boards, many of them I salvaged from samsung and sony TV's but theyre only worth about $20 or less. I usually post mine as the lowest price of them all but then sometimes it not worth the shipping hassle

[budm]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

You should put up a list of parts for sale.

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

Perhaps there should be a buy-sell forum on here for TV parts.

[budm]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

There is classified forum for selling parts: https://www.badcaps.net/forum/forumdisplay.php?f=12

[tom66]

Re: 40" Sony LCD KDL-40EX500 Seconds to black (6 blinks)

Marked as computer parts only...