Sony KDL-46NX810 No Video

[Gadjet]

Just got this one in, it's the first LED TV i've worked on.
When you hit the power button, the light turns green and the Sony logo below the screen lights up, but the screen is still black. Tried hooking up a dvd player to see if it was just the video but as far as I can tell there is no audio either
or ability to change the inputs. Let me know if I need to post pics of anything. Thanks.

[drpj23]

Re: Sony KDL-46NX810 No Video

Pics are very nice.
Um I suppose check what voltages are going to the LED drivers and T-CON.
And make sure other voltages are checking out too.
Check the smd fuses on the main board and T-CON too.

Is there still an image? (Shining a light at the screen)
If you disconnect the LVDS cable from the T-CON does the backlight come on?
Make sure connectors are snug (especially the ribbon to the panel from T-CON)

[Gadjet]

Re: Sony KDL-46NX810 No Video

Ok here are some pics or the main board and PSU, anyone know where I can find the service manual for this model? or how am I suppose to know what voltages I'm looking for? I know with plasma tv's the voltages are on a sticker on back of the lcd somewhere. I'll also post some of the TCon and Backlight.

[drpj23]

Re: Sony KDL-46NX810 No Video

The voltages should be on the board itself next to the connectors.

If you do want the service manual, all it has is the codes and schematics. It does not have a troubleshooting guide. Training guides have that (well extensively as compared to SM's and in this case only).

Here is a link to the manual (I made the link so it's safe), it's too big for this forum so I had to upload elsewhere otherwise you can't find it.
http://www.mediafire.com/view/?gabzwqdu0r02rxx

[Gadjet]

Re: Sony KDL-46NX810 No Video

Thanks for the manual, I added a few more pics of what happens when I turn the tv on and off. used a flashlight can't see anything.

[Mt.Man]

Re: Sony KDL-46NX810 No Video

When you loose video, does the TV shutdown? If it shuts down does the power LED blink? And if blinking how many blinks?

[Gadjet]

Re: Sony KDL-46NX810 No Video

Thanks for the reply, I'm not losing video I'm not getting any video at all when the power turns on nothing happens no blinking LEDs or anything. It's green as if everything is working okay.

[drpj23]

Re: Sony KDL-46NX810 No Video

Are the voltages checking out OK? and are there voltages present on the power supply even if the tv is in standby?

[Gadjet]

Re: Sony KDL-46NX810 No Video

Voltages look right, all of the 12v ones came up 12.53v. and no the voltages don't show when it's in standby.

[drpj23]

Re: Sony KDL-46NX810 No Video

Ok, what are the voltages coming out of the power supply to the backlight?

How are the fuses on the T-CON and Main? (If you have a hard time finding them include high def pics and I'll help you because they are sometimes incognito against the other components)

[Gadjet]

Re: Sony KDL-46NX810 No Video

Sorry about the delay, yes I need help identifying the the fuses on the T-Con and Main Board. Pics of the Main are at the top and I'm including pics of the T-Con now.

[budm]

Re: Sony KDL-46NX810 No Video

Pictures are way out of focus, I can see two fuses on the T-CON board.

[Gadjet]

Re: Sony KDL-46NX810 No Video

I took a few more hope these are a little better. I checked the 2 budm circled, and the ones on the inverter.

[drpj23]

Re: Sony KDL-46NX810 No Video

I found some on one of the main board pics. (circled in red...there are 3)

Basically you are looking with a component prefix of "F" and accompanied by an amperage rating. Sony's arrows are sometimes ambiguous though.

Also there will be some on the other side of the main board.

[budm]

Re: Sony KDL-46NX810 No Video

Since you see some of the fuses now, next thing is to find out if they have any voltage on them with reference to the chassis ground.

[Gadjet]

Re: Sony KDL-46NX810 No Video

Ok so I replaced the BUHT main board and now the red led comes on for a few sec and I start getting this 2 flashing leds.

the green power led and the amber picture off/timer led

[drpj23]

Re: Sony KDL-46NX810 No Video

Does that happen consecutively or with the power button?
How many times do the two LEDs flash?
And does the SONY logo still light up?

[Gadjet]

Re: Sony KDL-46NX810 No Video

Continuously as far as I can tell there are no breaks in between the flashing. and Yes the logo still lights up when you turn on the power then goes out once the Led start flashing.

[drpj23]

Re: Sony KDL-46NX810 No Video

All I can really say is get a T-CON and try that with old and new main......otherwise I have never seen that before.

But to be sure, list the voltages off the power supply in respect to the legend.
Example
Pin 1 - 12v - 12.56v

[Gadjet]

Re: Sony KDL-46NX810 No Video

Ok update, I disconnected the ribbon that goes to the Tcon to the BUHT and hit the power just to see what would happen and the screen lit up and started changing colors so I figure it's some type of self-diagnostic test. Red led was still on then after about a min the screen shuts off and flashes 5 times.