Sony Bravia KDL-37M4000 doesn't turn on

[winterwar]

Re: Sony Bravia KDL-37M4000 doesn't turn on

I swapped the old inverter back in. The 6X blink code is back. I get a green power LED for about 5 seconds and the TV shuts off, then the blink code starts. On pin 3 I get .27V off and 1.92V on.

With the 100 Ohm resistor installed I get the green power LED on continuously, no shut down. On pin 3 I get 0V off and on. The TV still doesn't do anything.

I don't know what I was doing last night when I first put that resistor in, but somehow I was managing to bypass it when I was checking the voltage readings... DUH!

[budm]

Re: Sony Bravia KDL-37M4000 doesn't turn on

So some how the new board did not activate the 6-blink, the old one does because it has an error output to pin 3 and you are able to ground it out with the resistor. So we know for sure that the old has problem, just do not know where. I would you to keep the old board and the resistor in place but disconnecting the Dimmer control wire, I believe it is on pin1 of CN4003 to see what happen.

[winterwar]

Re: Sony Bravia KDL-37M4000 doesn't turn on

I disconnected pin 1 (Dimmer) to CN4003. With resistor I get 0V on/off. Power LED glows steady green. Without resister I get the 6X blink error and power shuts off after about 5 seconds.

[budm]

Re: Sony Bravia KDL-37M4000 doesn't turn on

Ok, so still no backlights, for sure now you do have inverter problem, but the new inverter board may not be good either.

[winterwar]

Re: Sony Bravia KDL-37M4000 doesn't turn on

That figures... I can see about exchanging the new one for another one to see what that happens then.

Still no idea why the new one doesn't trigger the 6X blink error?

[budm]

Re: Sony Bravia KDL-37M4000 doesn't turn on

No not at all since all it needs to trigger the 6-blink is the HI voltage at pin 3 to trigger.

[winterwar]

Re: Sony Bravia KDL-37M4000 doesn't turn on

I'm going send new inverter back for exchange and go from there. Also, I think I'll keep an eye out for another main board that is reasonably priced. I haven't been able to find an exact match yet though. ShopJimmy is out of them, as are a couple of other places I've checked. I'll button this one up for now and come back to it later.

I picked up a 37" LG the other day that has some kind of problem that causes it to have to warm up for 20-30 minutes before it starts working. Maybe that one will be easier to figure out.

Thanks again for all your help on this Sony so far, Bud! I definitely learned a few things!

[budm]

Re: Sony Bravia KDL-37M4000 doesn't turn on

Your TV problem really bugs me and I just cannot figure why it is doing what it doing right now. I hope we can figure it out some how.

[heavymachines]

Re: Sony Bravia KDL-37M4000 doesn't turn on

Hi all been working on this same set and i followed all these steps in this thread and still not sure either. i was able to force power supply on and no backlights. yes with main disconnected. I did ground on cn4003 pin 3 with 100 ohm resistor to chassis and dimmer wire disconnected and still nothing and blinks the same 6 error code. Safe to assume inverter is junk or should i do some more testing? Thanks guys for any input.

[heavymachines]

Re: Sony Bravia KDL-37M4000 doesn't turn on

Well not sure, this being a sony and weird. I am not sure to rule out either main board or inverter. I would think forcing power supply to hold 24v to inverter would give me backlights. Nope. But is there something i am overlooking to trick the inverter itself to turn on or no? I know most of time when you force power supply on lg or sammys backlight come on, but not sure on this set Budm i know this is an old thread but you said you were curious to figuring this set out well now is the chance.



Grounding out pin 3 on n4003 with 100 ohm resistor does nothing still 6 blinks.
Disconnecting the dimmer wire pin 1 on cn4003 does nothing still 6 blinks.
Both 1 grounded out with 100ohm pin 3 on n4003 and dimmer on pin one does nothing still 6 blinks.

disconnecting main entirely, jumping pin ps_on pin 1 to stby pin 3 on power supply does turn on ps and feed 24v to inverter still no backlights so with that being said did i answer my own question and it is inverter or is this a haunted sony?

[heavymachines]

Re: Sony Bravia KDL-37M4000 doesn't turn on

UPDATE!!!!! it was indeed bad inverter TV works good again.

[budm]

Re: Sony Bravia KDL-37M4000 doesn't turn on

Thanks for the follow-up.