Sony 40 in LCD, no video no sound.

[SS_Pearl]

Ok, I found this forum and it looks like you guys really got it goin' on! Tons of good info. ...but I don't see any threads about my specific TV, I picked up this TV for free (because it doesn't work,), and was hoping it was a simple fix. Ok, I'm at work (sshhhh don't tell anyone) so, I don't have the complete model number. I know it starts with FWD-40..... (and I believe might be this one FWD40LX2F/B ) but I thought I would submit a new thread and start the ball rolling I know I'm supposed submit pics and so forth and will gladly do that when I get home. The problem with this unit is, no video and no sound. When I plug it in and flick the power toggle, I get a steady red indicator light, no flashing code, no green for a second, nothing. It does appear to have the backlight working. I can see it flash when I turn it on. Also, I get no menu or anytype of display when I click the menu button on the TV. The remote does power it on and off but that's about it. I haven't torn it apart yet, just because I wanted to first find a forum or a repair manual source or some other good info to feed on. - And I think I found it here. If you have any up front suggestions, I'll be gald to try them.
thank you in advance.

[SS_Pearl]

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

FWD-40LX2F is the actual model number. Here's some pictures with the back off the TV. First picture is of the whole tv with the back off. The second picture is apparently the power supply. The third picture is of the digital video board.

[SS_Pearl]

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

We disconnected and reconnected all connections to the boards, and confirmed the backlight comes on along with the green power indicator light. Tested with HDMI from a PS3 and no video and no sound....... Anybody?

[tom66]

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

Post a close up pic of the power connector on the power supply, which goes to the main board.

Usually no video/sound means a bad main board.

[SS_Pearl]

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

I think this is what you're talking about....

[tom66]

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

Good - is there a legend next to the pins?

[SS_Pearl]

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

The only label next to the pins are as follows:
As you see it in the picture
- top connection CN931
- bottom connection CN950

[tom66]

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

The only label next to the pins are as follows:
As you see it in the picture
- top connection CN931
- bottom connection CN950

Remove the board and flip it over. Is there a legend on the other side?

[SS_Pearl]

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

AH, ok, I'll do that when I get home from work.
Now, just asking, I see many threads where the t-con board has failed, I only see the two boards on this TV, and from researching the model #s off the boards, one is the power supply and one is the digital video board (main board or A board as I see they are called), ...is there a t-con board and could that be the issue? And how can I test if the juice coming out of the power board is correct? I have a digital meter. (although I'm not too great at understanding electrical readings). I can test continuity and voltage.
thanks

[randtek]

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

T-Con board normally would not kill your sound. Sound does not go through T-Con board.

[SS_Pearl]

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

Looking at this model specs again, this actually is listed as a monitor, not a TV. It might not even have speakers. This may be a mute point. I suppose I could hook it up to HDMI and run everything thru that, and my reciever would handle the sound, but now if it doesn't have speakers then maybe it is the T-con board.???? well, first thing first. we'll keep trouble shooting and see if we can get it working, but not having any sound might be just that it doesn't have speakers. All I was doing was hooking up HDMI.

[tom66]

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

Looking at this model specs again, this actually is listed as a monitor, not a TV. It might not even have speakers. This may be a mute point. I suppose I could hook it up to HDMI and run everything thru that, and my reciever would handle the sound, but now if it doesn't have speakers then maybe it is the T-con board.???? well, first thing first. we'll keep trouble shooting and see if we can get it working, but not having any sound might be just that it doesn't have speakers. All I was doing was hooking up HDMI.

It does have some speaker jacks on the bottom - try connecting standard hi-fi speakers to it...

[rayrod81]

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

I recently fixed a Sony TV with this same exact LCD panel. It had backlight and sound but no picture. The fuse on the T-Con was blown. I replaced the fuse and it has been working for 8 days now. It is a 32V 3 Amp fuse. It is a micro SMD fuse so it is not the easiest to replace. It is possible that you could have the same problem but you would have to test the fuse for continuity to know for sure. If the fuse is blown then replacing the T-Con would be the easiest solution.

[SS_Pearl]

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

Rayrod, ok - see previous post, not sure where the t-con is. I only see the two boards. Power and video. Where would it be, is it the one under the metal, on the left side as you're looking at the back????

[tom66]

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

There is a T-con board under here. Trace the connector.

Unfortunately, it looks like you'll need to remove the metal frame to get at it.

I've repaired an Acoustic Solutions (cheap no-name) TV with a Samsung LCD in it - that had a bad fuse on the T-con. Symptoms were no video (but backlit) but good sound. AFAIK, Sony use Samsung LCD panels (S-LCD: Sony/Samsung joint partnership.) The Acoustic Solutions required the removal of the entire metal back frame to get to the T-con.

[PlainBill]

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

Rayrod, ok - see previous post, not sure where the t-con is. I only see the two boards. Power and video. Where would it be, is it the one under the metal, on the left side as you're looking at the back????

In the first picture there is a black cable coming off the upper end of the main board and going under a metal cover. That goes to the tcon.

PlainBill

[SS_Pearl]

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

Ok, I hooked up a speaker and powered it up -plugged in an hdmi cable from the PS3 and went thru the inputs (I think, again, no way to tell when there is no display or anything for me to tell...) so I would say at this point, no video and no sound. If I knew where the T-con board was, I could check the fuse...if I knew where the fuse was ON the t-con board. There was a fuse on the power board, and I checked that for continuity and it shows o.2 on the ohm meter.
Thanks again for everyone's help!!

[SS_Pearl]

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

Ok, posted before reading the two previous..thanks, will check. Once I get to it, where would the fuse be and what does it look like. I take it that it must be pretty small.

[tom66]

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

Ok, posted before reading the two previous..thanks, will check. Once I get to it, where would the fuse be and what does it look like. I take it that it must be pretty small.

A little white ceramic object, 0.12" by 0.063", with tinned metal leads on either side. Sometimes smaller. Usually right next to the connector.

[SS_Pearl]

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

Ok, sounds good. Will check for it. I know what a normal fuse would look like when it fails, but will this have any indication that it's bad? WIll I have to test it with the meter?