Sony 40 in LCD, no video no sound.

[retiredcaps]

Re: Sony 40 in LCD, no video no sound.

WIll I have to test it with the meter?

A good fuse will measure less than 1.0 ohms. You can't tell if it is good or bad just by looking at it.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Ok, here are some pics after pulling the metal off to get to the t-con board. The first is of the T-con board front then the next three are of the power board, I was looking for the legend that tom66 wanted, but after removing it and flipping it over, I don't see any other lables or legends, no writing of any kind actually. BUT, did notice that two solder leads looks like they were burned or discolored in some way. close up of the back in the third pic and then flipping it over I see this little green little guy standing in the center of the forth pic-... that after doing a little research...isn't that a fuse???? It has a symbol under it which looks like a zigzag. (Sorry about the quality of that last pic, a little fuzzy-but you get the idea)
Thanks

[tom66]

Re: Sony 40 in LCD, no video no sound.

Let's focus on the T-con as it's the most common cause of this problem. Here are some tests to perform.

The red circled object near the connector is a fuse. Test using your ohmmeter on your multimeter; it should measure less than 1 ohm. (Do not confuse this with a single "1" on the left hand side, on many meters this indicates out-of-range, *not* 1 ohm.)

The other two circled objects are diodes. Using the diode mode (kind of looks like -|<-) you should measure around 150-600 one way, and infinite the other way. It's only necessary to test one, as they are both in parallel.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Ok, the fuse shows nothing on the ohm meter. (standard 1 like you said...basically no change when i touch each side) the two diodes test at 195 one way and infinite the other way. So the fuse is blown? Can I jump it and test...somehow?? Or just replace the board?

[tom66]

Re: Sony 40 in LCD, no video no sound.

Ok, the fuse shows nothing on the ohm meter. (standard 1 like you said...basically no change when i touch each side) the two diodes test at 195 one way and infinite the other way. So the fuse is blown? Can I jump it and test...somehow?? Or just replace the board?

The diodes are good.

I wouldn't advise it, but if you're willing to risk it, a blob of solder would work as a temporary fix, but would highly advise replacing with a new fuse asap.

As I see it there shouldn't be a major issue, as the board regulators and power supply are usually short circuit protected. The fuse might be there to allow the TV to function correctly (albeit with no picture) during a T-con fault, allowing for easier diagnosis. Or maybe it's to prevent damage to the thin LVDS wires which probably can't carry more than 1A each.

I confess to have jumped a fuse on a T-con before on a cheap TV with a similar T-con, but I replaced the fuse before assembling it.

If you do decide to jump the fuse and it doesn't work within about 15 seconds, unplug the TV immediately.

What is the marking on the fuse? Should be a single letter.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

The letter on the top of the fuse is "P". So lets say I don't want to chance jumping it with a blob of solder, where can I get another fuse? Or, again, should I just replace the board? Are we certain that it's the fuse, can't be something else? (so I don't waste $$ on a T-con board?).

[tom66]

Re: Sony 40 in LCD, no video no sound.

The letter on the top of the fuse is "P". So lets say I don't want to chance jumping it with a blob of solder, where can I get another fuse? Or, again, should I just replace the board? Are we certain that it's the fuse, can't be something else? (so I don't waste $$ on a T-con board?).

I have replaced just that fuse before and it fixed the problem.

P is a 3A fuse. Here are some: http://www.ebay.co.uk/itm/20pcs-Litt...item256857bb56

[rayrod81]

Re: Sony 40 in LCD, no video no sound.

It is a 3A/32V fuse. It is the problem. To test just bridge it with solder and turn it on. If you get picture then that will confirm it is the fuse. You can buy a fuse from Digikey. Just measure it with calipers and you can find the one you need on the website. Don't run it for a long time with the solder bridge. Just run it long enough to confirm you get a picture.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Is this the little bugger that I need?
Digikey 3A 32VAC Surface Mount Fuse

[tom66]

Re: Sony 40 in LCD, no video no sound.

Is this the little bugger that I need?
Digikey 3A 32VAC Surface Mount Fuse

Yep, but that has min order 5,000... Try this: http://search.digikey.com/us/en/prod...32CT-ND/686742

No minimum order, 35 cents each. They are tiny, get two or three because you can so easily lose them on the floor or your workbench.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Wow!! 5,000, yeah, might not need that many. I thought you got a price break at 5,000. Ok, we'll give it a shot and see what happens.
thanks

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Ok! Received the fuses. Soldering that little thing was fun. Finally got it, SUCCESS! Video works. Unfortunatley not getting any audio. I hooked 5 different speakers to it just to make sure and not getting anything. Any ideas? Thanks for everyones help so far.

[tom66]

Re: Sony 40 in LCD, no video no sound.

Ok! Received the fuses. Soldering that little thing was fun. Finally got it, SUCCESS! Video works. Unfortunatley not getting any audio. I hooked 5 different speakers to it just to make sure and not getting anything. Any ideas? Thanks for everyones help so far.

Enjoy...

Could be muted?

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

I thought that might be the case, so I got the remote out and checked. Nope, my life couldn't be that easy.

[tom66]

Re: Sony 40 in LCD, no video no sound.

I thought that might be the case, so I got the remote out and checked. Nope, my life couldn't be that easy.

In the menus there is often an option for the TV speakers to be turned off (there is on my LG.) Otherwise, the TV probably has a line-level audio output, so you may need to use an external amplifier or surround system.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Ok, where would the sound stuff be, on the main board?

[tom66]

Re: Sony 40 in LCD, no video no sound.

Ok, where would the sound stuff be, on the main board?

Follow the cable from the speaker jacks, and post a photo of anything near this connector. Usually there are four small black or blue discs around a small chip. (This is a very efficient class D audio amplifier.)

[tom66]

Re: Sony 40 in LCD, no video no sound.

Manual says:
Speaker Out
“On”: Enables sound to be emitted from the speakers.
“Off”: Disables sound to be emitted from the speakers.

Also:

No sound/Noisy sound:
Good picture, no sound.
• Check the volume control.
• Press [MUTE] on the remote control or + so that “Muting”
disappears from the screen (page 13).
• Check “Common Audio Sel.” settings (page 24).
• Check “Speaker Out” settings (page 24).

and Common Audio Sel.:
Common Audio Sel. “HD15”: Outputs audio from a piece of video equipment or PC connected to the
HD15 (RGB/COMPONENT IN) connector and the AUDIO (COMMON AUDIO
IN) connector.
“HDMI 1”/“HDMI 2”: Select to connect a piece of equipment using an HDMI cable
(not supplied) or an HDMI-to-DVI cable, and the corresponding audio cable at the
same time.
See page 8.
Notes
• When using an HDMI-to-DVI cable (not supplied), connect the audio cable to the AUDIO (COMMON AUDIO IN) connector.
• When “HDMI 1”/“HDMI 2” is selected, digital audio is not output from the HDMI connectors. When a piece of video equipment equipped with an HDMI connector is connected to the HDMI 1/HDMI 2 connectors, set “Common Audio Sel.” to “HD15”. (The default setting is “HD15”.)

Hope this helps.

Manual is here: http://www.sony.co.za/product/fwd-40lx2f#manuals

Also, check all power connectors are properly seated; maybe one carries the power for the audio amplifier.

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Ok, Tom66, I think you found it. I did all that is mentioned above except that last part (Common Audio Sel). I had the HDMI from the PS3 hooked up to HDMI1 and selected that from the menu for the sound out -and figured that the sound thru the HDMI would go thru the system and be played on the speakers. So, I will select the HD15 and see if that works. I may have tried it I can't remember. Thanks fo rthe manual link. ...and will check power connections again. Thanks!

[SS_Pearl]

Re: Sony 40 in LCD, no video no sound.

Ok, this pic is from the original posted at the beginning of this ordeal. The arrows show the cable going from the speaker connetions to the main board. This pic shows the cables not connected, but everything was put back for the final test. I will double check the connections and post close-up of the connection at the main board. Can I put a meter on the speaker connections and see if I'm getting anything?? Or is there somewhere else that I could test?
Thanks