Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

[kevinm34232]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

Correct I did disconnect those ribbons,I just need to make sure that when I did that, I had the LVDS cables reconnected which I'm pretty sure I did but I will recheck.

I am talking about the two flat cables between the T-CON and the panel, not the two flat cables between T-CON and the main board.

[budm]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

I tried that first and there is no change.

I am talking about the two flat cables between the T-CON and the panel, not the two flat cables between T-CON and the main board.

[budm]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

So if you leave the T-CON force on in place, you still get 5 blink codes?

[kevinm34232]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

I'm 99% sure I tried that first and there was no change but I will confirm again.

What is the LCD panel model number? I can see the white sticker on the panel but the picture is not clear enough to read the numbers.
BTW, what happen if you disconnect those two cables between the LCD panel and the T-CON board?

[kevinm34232]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

I will have to get the part #s when I get back home.

As far as the T-Con ON signal, the main board is not sending it. I can hit the power button while Im getting the 5 blinks code, and Power ON will go to 3.3V for a second, but nothing on the T-Con ON.

However if I apply 3.3V to T-Con ON, I do get the T-Con 12V so power supply is good.

[Andrew F. Ali]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

Also what is the T-CON Bd Part No. on the white sticker at the bottom of the board?

[budm]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

What is the LCD panel model number? I can see the white sticker on the panel but the picture is not clear enough to read the numbers.
BTW, what happen if you disconnect those two cables between the LCD panel and the T-CON board?

[Andrew F. Ali]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

The T-CON ON signal comes from The Main Bd. and tells the PSU to supply 12V to the T-CON Bd. I wanted to verify the Main Bd. was OK. 5 blinks is T-CON Bd problem. So then if the Main Bd. produces the T-CON ON signal and the PSU produces the 12V to supply the T-CON but when it reaches the T-CON Bd. a problem on the T-CON shuts down the PSU. OR the Main Bd. is not sending the T-CON ON signal to the PSU and so the T-CON never gets powered and so the system says T-CON Bd. problem. BTW I was getting 7 blinks which pointed to a Main Bd. problem but when I tested the PSU it was bad and so got anew PSU and the TV came on and work perfectly. So sometimes the blink codes do mislead us.

[kevinm34232]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

I tried unplugging the cables to the T-Con board with no change, but I assumed it's looking for a signal from the T-Con and if it doesn't get it, it won't send T-Con ON?

I downloaded the firmware file I was gonna try that when I get back to it..

Do we know what it's checking on T-Con board to give the T-Con ON signal?

[Andrew F. Ali]

Re: Sony KDL-46EX640 won't turn on, 5 blinks on standby light.

There would be two flat cables coming off the Main Bd. to the T-CON Bd. Unplug them, carefully, from the T-CON Bd. and try a turn ON. If voltages come up and are steady then the Main Bd. might be OK. I have attached the SM for you. I repaired two of these recently. One was a PSU issue and the other was a double image, I fixed on the T-CON Bd.

[kevinm34232]

Hopefully someone is familiar with this model/series. I couldn't find a SM or much online, except that 5 blinks seems to be T-Con error. I checked T-Con fuse and surrounding diodes and they are good. I disconnected the LVDS cables, same. Next I disconnected ribbons to the panel, same.

I disconnected main board, and forced POWER ON, and BL-ON, and backlights come up and all voltages normal. When I force T-Con ON I get 12V on the T-Con-VCC-12V. So power supply seems fine.

With main board hooked up, I'll get a short voltage at POWER ON when hitting the power button. But never any voltage at T-Con ON.

Also, I get 3.3V at BL-ERR, is that supposed to be high when working? Backlights do come on steady when forced on..

So I'm not sure if there is actually some problem on the T-Con, or there is a main board issue...

Any ideas? Thanks!