Philips 40PFL9705 T-con 9 blinks

[trunks81]

Hello

Ive got two screens of 40PFL9705 wit both bad tcons i think.
I allready replaced Fet FDS8880 and FDS 8813NZ
And i still getting the nine blinks,
What could be an option is that both fets are defective again
But iam out of options

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

do you have a short circuit on C1222?

Greetings Thomas

https://forum.iwenzo.de/philips-40pf...r--t70475.html

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

iam getting 35 ohms over that cap

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

Replaced that cap but still an short

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

Exactly the same problem as me. I am in the link to the German forum. Problem is IC302. The BGA causes this short circuit due to contact errors. Unfortunately I have to wait for my delivery from China before I can continue. BGA must be reballed.

Greetings Thomas

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

Oh yes, one of the FDS has a short circuit again. Check that too, because then it must also be renewed.

Greetings Thomas

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

do you have an link for that stencils you also ordered ?

[Davi.p]

Re: Philips 40PFL9705 T-con 9 blinks

Why do you changed that 2 mosfets?

Problem is IC302. The BGA causes this short circuit due to contact errors.

This sounds not to be correct, a missing of a signal can't build an overcurrent, furthermore them are smps converters so them are surely protected against overcurrent. The upper mosfet in the couple of the photo usually fails, i have substituted the FDS8813NZ with IRF8734PBF. Don't get them directly from Chinese market, Chinese people are like the Devil, you probably get fakes, get them from your Country's professional suppliers, and i have also substituted the surroundings electrolytics 1x220u2,5v, 1x22u20v, 1x39u10v, them marked well on my esr meter but i'm unsure of them, probably are the main cause. If it is not so then is a power surge.

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

That can be with you. After removing the BGA, I saw the problem.
Now the short circuit is gone and the BGA is also OK. The capacitors are all OK with me. I just have to wait for my material until I can continue.

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

Are you going to use an template for reballing ?

[Davi.p]

Re: Philips 40PFL9705 T-con 9 blinks

But 35ohms is not a short. The 2 fets provides the Vcore supply for the 2 big BGA, if i remember it's something around 1v. I don't remember, for the FDS8813NZ does its Drain is connected to the 12V-in? IF yes the 12V can reach the BGA. The contemporary fault of the FET and the BGA makes no sense to me 'cause if the BGA goes short the SMPS circuit surely has a SC protection and it doesn't break. Here the OP must clarify if he has found SC on the FET after removing it. The common fault on theese boards is an intermittent SC on that FET that makes image to disappear and TV go into standby in error.

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

For me it will be a first. Otherwise I had someone else do the BGAs. But it is getting more and more and now I want to try it myself. I ordered various items. Also heat stencils, flux etc.
LG Thomas

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

I know that 35 ohms is not a short circuit, but if I now connect the Tcon without BGA, the FET will heal. I will see it when I have installed the BGAs what happens. I have to wait until then. Unfortunately there are no data sheets either.

LG Thomas

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

Which heatstencil did you order ?

[thommyX]

Re: Philips 40PFL9705 T-con 9 blinks

https://de.aliexpress.com/item/18776...archweb201603_

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

Today ive got an used board from aliexpress,
First thing i noticed is an green stuff on those mosfets.
So cleaned it up and hooked the board in the tv now the tv starts and ambilight goes and sound is there, but still no image only backlight
Now the tv gives 3 blinks instead of 9

On this board the caps measure 50 ohms

[Davi.p]

Re: Philips 40PFL9705 T-con 9 blinks

How much $?? I don't know why you are not listening to someone (me) that had repaired 4 of them.. instead thommyx i don't know how many..

[petehall347]

Re: Philips 40PFL9705 T-con 9 blinks

FDS8880 needs soldering properly .

[trunks81]

Re: Philips 40PFL9705 T-con 9 blinks

Oke going to replace those fets again. They came from ebay so probably its from china.

[Davi.p]

Re: Philips 40PFL9705 T-con 9 blinks

there's no "Farnell","RS-components","Conrad" etc.. in your country? Get IRF8734PBF instead...