Sony KDL-40V4100 no display

[Mr Bill]

This is a co-workers tv. When i first turned it on about 3-4 inches on the far left side was black with a few multicolored lines in it kinda like a bar code. If i pressed the menu button you could see some of the menu box, atleast what stuck out beyond the black. I wiggled the tcon cable as suggested in budm's sony tcon pdf to see if a change in the screen would happen.

But here is the odd thing. When i wiggled the cable to get a reaction (which it did), the whole tv just shut off and then turned back on (rebooted). I had a wtf moment and now i am not getting any display at all. Audio is still present. I checked the fuses on the mainboard and they all test ok. The fuse on the tcon board is good too. BUT, i am not getting 12v to the tcon from the mainboard.

So, in a nutshell is the tv even worth looking into considering it had the black on the left side. I remember reading a couple posts that this is a common failure among these tvs (lcd panel).

The voltages coming from the power supply are all spot on. If anyone has had any expierences with the KDL tvs please post your story.

Thanks

[tibimakai]

Re: Sony KDL-40V4100 no display

Do you think that you shorted something while you were wiggling that cable?
I would try fixing it, even if the panel has that famous issue. Maybe you can fix it with that resistor and wire fix.
Last time when I played with the flex cables while the TV was on, I have blown a fuse on the mainboard, but that was a Vizio.
I had a W series on which all I had to do is a factory reset, it had the restarting issue, then an error code 10. Resetting to factory it was arrow up on remote and power button on the TV if I remember well.

[Mr Bill]

Re: Sony KDL-40V4100 no display

I double checked all the fuses front and back of the main board and they are all reading good. Can you explain the resistor and wire trick?

[tibimakai]

Re: Sony KDL-40V4100 no display

http://www.youtube.com/watch?v=TccQ2...eature=related
there should be an English version somewhere.
We have discused this issue in the Vizio VW42 thread started by me.

[Mr Bill]

Re: Sony KDL-40V4100 no display

Well i rechecked the fuses and i missed one
Put a blob of solder over it and i'm atleast back to square one. I'll look into the wire and resistor fix. Does this seem like a candidate for it?

Thanks

[tibimakai]

Re: Sony KDL-40V4100 no display

try flexing the frame, see if it makes a difference. I'm not an expert, but I would check some parts out on the t-con also. Did you cleaned the ribbons, reseated all the cables?
The tab issue would cause a dark area on one side and ghosting.

[cashkennedy]

Re: Sony KDL-40V4100 no display

The 32" is the most common model that gets the ghosting / darkness issue that is fixable by the 10ohm resistor method. Im the first person to ever try it on a 40" and it worked to fix my kdl-40s5100 (made in 2009).

The symptoms are ghosting across the whole screen and a darker picture then normal (but this is hard to tell as many of these sonys have issues with the dyanmic contrast enhancer)

One thing ive noticed is if you ground any of the voltages created by the tcon it will shut off. So most likely your twisting the tcon grounded a voltage.

Getting lines on the screen could occur from a bad tab bond (similar issue to the one the resistor fixes), but it could also be other things like too much pressure being applied to the screen / bad tcon). I think usually lines from a bad tcon have a pattern (see budms pfd on common tcon failures).

Yours is missing such a huge portion on that side that id say your whole tab on that side is disconected. Do you know if anyone else took the tv appart to look at that tab? though heat can loosen one compleatly by itself. You dont risk much taking the tv completly appart except your time. Its a fairly light 40" tv too, so hopefully wont break your back taking it appart.

Your model looks 100% identical to mine btw , so if you want a tcon pretty cheap for testing, tell me what the model number is on yours, cause i still have the extra one i bought to test if that was the problem with mine before i realized it was bad tab bonding.

[Mr Bill]

Re: Sony KDL-40V4100 no display

I disassembled the whole screen this morning and the tabs are all connected. Pushing on the tabs does nothing.

The tcon is:
T400HW01 V5
40T02-C06

The panel itself is a AU Optronics. Took me almost 35 minutes to find one that the seller actually had one in stock ($49.95 ) I am hoping but i'm not holding my breath.

[tibimakai]

Re: Sony KDL-40V4100 no display

That Sony that I have started asking about a while back(same model as yours), reappeared on craigslist with a 8" wide solid black line close to the middle of the screen.
I would like to know myself what is this to know if it's fixable. Not sure to pick it up or just let it go.

[tibimakai]

Re: Sony KDL-40V4100 no display

The person sent the picture:

[cashkennedy]

Re: Sony KDL-40V4100 no display

The tcon on mine was NP_HAC2LV1.1 or something along those lines.

I had a chungwa or samsung panel as far as i could tell, deffinetly not an AUO. AUO is pretty high quality and isnt responsible for either of the faulty tab bonding issues common with sonys.

I think these ones with the large stripes missing might have bad resistors on the tabs, ive never had to do that repair, but theres a common repair like that. Ill try to find a video or more info on that when im home.

[tibimakai]

Re: Sony KDL-40V4100 no display

it almost looks like when do you disconnect one of the ribbon cables, but doesn't go out half of the screen. It can't come from the T-con?

[cashkennedy]

Re: Sony KDL-40V4100 no display

Im not 100% sure, but if you look at budms learn about tcons page (and its pdf from sony on detecting tcon failures) there is a picture of what happens if one of the tcons drive output fails (you get a stripe every inch or so (probably every 100 pixels or so, so around 19 of these thin 1 pixel stripes) This makes me believe that the tcon output channels handle the data for every 20th column and not a whole chunk in the middle.

And as i said these failures with huge stripes missing are almost always are from a part on the thin boards along the edge of the lcd, or a part mounted on the tabs.

[tibimakai]

Re: Sony KDL-40V4100 no display

whould you get this TV?

[cashkennedy]

Re: Sony KDL-40V4100 no display

I wouldnt get it unless you find a guide explaining how to fix it / test for the problem and mr bill says the repair seems feasible and does see the problem.

[cashkennedy]

Re: Sony KDL-40V4100 no display

My apologies, although there are lots of videos on youtube about fixing similar black lines, they all apply to plasmas. So unless those models are plasmas (im pretty sure theyre not), then it might not be an easy repair.

[retiredcaps]

Re: Sony KDL-40V4100 no display

whould you get this TV?

When I invest my money, I try to emulate the best like Warren Buffet. One of the secrets to his success is that he only swings at the fat pitches in baseball terms.

He doesn't swing at the low and outside, high and tight, he only swings at the pitches in his comfort zone. Best of all, he can never be called out on strikes as there are always pitches coming (i.e. the stock market is open all the time). This, obviously, requires a lot of discipline and patience. Sometimes Warren doesn't make an investment for years.

This is no different from the Fluke 179 going for $150 on craigslist that you are considering. I believe it is too high priced for that meter. With patience you can either get the same multimeter for $100 or get a Fluke 87V for $150 IF you have patience. While $50 may not break your bank, these habits go a long way to helping you invest, buy stuff on ebay, negotiate for other items, etc.

Examples of recent 179s sold

NEW for $100
http://www.ebay.com/itm/261003913376

$102.50
http://www.ebay.com/itm/140739304983

$77.50
http://www.ebay.com/itm/ws/160783421123

So deciding on whether to buy a broken TV for repair and then reselling it is the same idea. Choose the "low hanging fruit ones" and leave the tough ones that require lots of time, parts and money to someone else who doesn't have the same discipline.

PS. You might want to check out the Fluke 79 III auction

http://www.ebay.com/itm/280868315050

I think $50 is a fair Buy It Now price for this multimeter. In fact, I'm quite surprised the auction is still running because I thought someone who had hit BIN pretty early. It is the predecessor to the Fluke 170 series.

The Fluke 79 III has True RMS, touch hold, analog bar graph, 4000 counts, and capacitance measurement. All are practical features that you would use daily to troubleshoot TVs and electronics.