View Full Version : Trying my hand at an LCD TV repair....


Kamakiri
12-10-2013, 12:06 PM
Picked up a Sylvania 40" LCD set for free, so I thought I'd give it a go for the heck of it :)

It's a model LC407SS1, and has a picture similar to this:

http://i32.tinypic.com/3zwhv.jpg

No audio, but I don't know if the menu settings are set on one of the HDMI ports or something. Pulled the back, and while the set is on, there is a peculiar ticking sound from the T-con board. Unplug the T-Con board, and the screen is black and even, ticking goes away. Might be in over my head, but the price of admission on this project is $0 so far :)

Jeffhs
12-10-2013, 01:40 PM
Picked up a Sylvania 40" LCD set for free, so I thought I'd give it a go for the heck of it :)

It's a model LC407SS1, and has a picture similar to this:

http://i32.tinypic.com/3zwhv.jpg

No audio, but I don't know if the menu settings are set on one of the HDMI ports or something. Pulled the back, and while the set is on, there is a peculiar ticking sound from the T-con board. Unplug the T-Con board, and the screen is black and even, ticking goes away. Might be in over my head, but the price of admission on this project is $0 so far :)

I don't know much about repairing LCD flat TVs except what I've read online, but I'll throw this in. If the ticking is coming from the T-con board, and the noise disappears with the board removed from the chassis, that board may well be the problem. Replace it. I wouldn't be surprised if this cures the trouble, and brings the set back to life. A replacement for this board is probably available from Sony's parts department; I'd check their website to be sure. Unless your TV is very old, I would think a replacement for any board in the set is still available.

As to the audio problem, I would check the menu settings, if you can get to them; I wouldn't be surprised if the speakers have been shut off. If there is an option on the main menu to reset the TV to factory defaults, use that option to reset everything. If the problem is caused by an incorrect setting, resetting to defaults should get things going again. This is the first thing to do when a flat-screen TV develops problems; if resetting to factory defaults doesn't cure the trouble, further troubleshooting is in order.

Good luck.



BTW, your screen shot shows a pattern similar to a bar code. I read online some time ago that this pattern is sometimes caused when the TV's internal software crashes. If your TV has a USB port, you can use a flash drive with the set's software loaded on it to replace the defective programming. Go to Sony's web site and look for a link to software updates to load the flash drive first; this procedure works with my Insignia flat screen, which has a USB port for software updates on the jack panel at the left side of the set. This port is likely on most other LCD flat sets as well, although on some sets it can be difficult to locate.

davet753
12-10-2013, 07:07 PM
I got out of the repair biz years before flat screens came out, but I have a friend who is still working at a TV shop. He told me that outside of replacing bad electrolytic caps or an open resistor, there's not much that can be repaired on the LCD sets. He did say they done a lot of "board swapping" (if they can even get a replacement board).

It makes sense to me. On CRT sets, the lion's share of problems come from the power supply and high voltage section....on the new flat screens, there is no high voltage for the CRT anode.

CoogarXR
12-10-2013, 09:54 PM
Those Funai sets (Sylvania,Philips,Emerson,Magnavox) suck to diagnose. Be careful when buying boards for them. They used whatever panel was cheapest that week. The power supply is usually the same, but the mainboard, panel and TCON can be completely different even in the same model.

Kamakiri
12-11-2013, 08:45 AM
I just went off the part number of the exact board that was in the set. Found a good used one on eBay for 18.99 with free shipping, so I figure that's worth a try.

Kamakiri
12-11-2013, 08:47 AM
BTW, your screen shot shows a pattern similar to a bar code. I read online some time ago that this pattern is sometimes caused when the TV's internal software crashes. If your TV has a USB port, you can use a flash drive with the set's software loaded on it to replace the defective programming. Go to Sony's web site and look for a link to software updates to load the flash drive first; this procedure works with my Insignia flat screen, which has a USB port for software updates on the jack panel at the left side of the set. This port is likely on most other LCD flat sets as well, although on some sets it can be difficult to locate.

It occurred to me that I've seen the exact same thing working on laptop computers, when there's a faulty ribbon cable or connection from the screen to the CPU. I checked all of the ribbon cables and re-seated them before ordering the TCON, and no change.

While I've never worked on one of these before, I would assume that the skill sets are a cross between laptop repair and TV repair. Guess we'll see....

Zenith26kc20
12-11-2013, 01:33 PM
AS mentioned earlier, these sets can use slightly different T-con boards even model to model. The audio IC's on these sets are generally so small they burn up from a loud listener. Definitly check the capacitors on the power supply. I don't take the Funai sets in anymore. The power supply caps fail and when replaced, the T-con board fails in a few days. That results in a very unwelcome comeback.

Kamakiri
12-19-2013, 09:23 AM
New T-con, no change.

Here's a shot of what I'm getting....damaged a little on the lower part, but I thought I'd see if I could fix it anyway....after all, the kids are only playing games on it :)

Pitch it or try caps?

Zenith26kc20
12-19-2013, 01:56 PM
Looks like the screen got whacked, especially the bottom. Common on a lot of flat screens. Wait till superbowl and the thrown remotes. The flat screens die from a remote aimed well. CRT sets make the remote splatter all over!

coppercity
12-19-2013, 05:40 PM
I would pull the power supply and other boards then pitch it, I agree the screen looks like it was shattered.

Kamakiri
12-19-2013, 07:13 PM
Can anybody use the boards? I'm not gonna screw with these again....

wa2ise
12-19-2013, 09:02 PM
Wait till superb owl and the thrown remotes. The flat screens die from a remote aimed well.

Flat screens don't do well with footballs thrown at them either... :no:

Sandy G
12-19-2013, 09:33 PM
Looks like Target Fodder to me...