Philips Plasma

[plumbcrazy]

I have a Philips plasma tv Model # 50pf7321d5 that I just replaced two bad caps. When I plugged it in and turned it on the green light at the bottom came on then flashes red four times. I noticed the power board has two green lights but the one on the right doesn't come on. I'm not sure what I should look at next any help would be appreciated.

[cashkennedy]

Re: Philips Plasma

You should post the model number in the subject of the thread.

Would be helpfull if you posted a picture of the power supply board. Only replacing 2 caps, is not usually recomended, since usually all the caps in the secondary of the psu will be a bad brand if 2 failed, and you cant rely on visual determination of bad caps, not all explode / leak.

Do you have a multimeter to check the DC voltages the power supply is creating?

[cashkennedy]

Re: Philips Plasma

Here is a service manual link for a set with 1 model number before it. Most likely the error lights / basic steps will not have changed.



make sure to read for the "This file is downloadable free of charge" part in tiny text, that is where the link is to the manual, once you wait a few seconds

4 short blinks followed by a 1.5 second pause = acording to that manual
"4 Genesis Scaler
Flash-ROM
I2C error while
communicating with
the Genesis Scaler
and/or Flash-ROM
is faulty/empty"

[plumbcrazy]

Re: Philips Plasma

Sorry that should say d37 not d5. I found a tiny burn the size of a pencil tip in the powerboard. I'm told it's not repairable so i'm pricing them out now.

[tom66]

Re: Philips Plasma

Probably is repairable... How about a picture of the damage?

[plumbcrazy]

Re: Philips Plasma

here is some pics of the damage i was talking about. I was told because it on a main power run it wasn't repairable.

[tom66]

Re: Philips Plasma

That is nonsense. There aren't even components there. A little bit of isopropyl and the mark will be gone. Who told you that -- a TV repair shop?

[plumbcrazy]

Re: Philips Plasma

An electrician i know. It goes pretty deep if that makes a difference. It's hard to see.

[tom66]

Re: Philips Plasma

I would class it as perfectly repairable but I don't know what would cause that. Anything on the top that's burnt?

[plumbcrazy]

Re: Philips Plasma

no, just that spot. isopropyl? rubbing alchol?

[tom66]

Re: Philips Plasma

Yes, rubbing alcohol will clean it, but you have other issues as that would not cause your problem.

[plumbcrazy]

Re: Philips Plasma

I was also told my solder probably didn't get hot enough. I should get a thinner wire with flux already in it. He thinks maybe i didn't get it hot enough to burn out the flux.

[tom66]

Re: Philips Plasma

Again that makes for very bad advice. You DON'T want to burn out the flux! The flux is embedded in solder for a reason, to ease soldering onto dirty materials. If your iron is way too hot, the flux will just evaporate and you can still solder but you'll get cold joints which are not fun at all -- your TV will work fine for a few months then stop working as the joint cracks. The smoke you see from your iron is in fact flux burning off -- a small amount is normal, but it should be kept to a minimum. All modern solder (1950s onwards) has embedded flux. Supplement only with additional flux for specific applications, such as surface mount and particularly bad metals.

I have a feeling an electrician should stick to wiring sockets, breakers and houses, not giving soldering advice, which is an electronics discipline.

[plumbcrazy]

Re: Philips Plasma

If my flux has embedded solder and i added flux as well could i have made a problem for my self. I can see flux residue on the board around my solder. My solder looks pretty crappy compared to what is already there.

[tom66]

Re: Philips Plasma

Isopropyl cleans that. Additional flux is rarely necessary for through hole soldering, on a power supply like this. Flux with embedded solder. Are you sure?

[plumbcrazy]

Re: Philips Plasma

Should I clean it up and try melting my solder a little better and then see if the tv responds.

[tom66]

Re: Philips Plasma

I'd give it a go, but if that doesn't work, we can go further with the troubleshooting.

[plumbcrazy]

Re: Philips Plasma

thanks for the help.

[cashkennedy]

Re: Philips Plasma

The area where that burn mark is looks to be the seperator line between hot and cold side of a power supply. The only components that cross that area are optocouplers, are you sure there isnt a small square black peice with 2 leads on each side of the box on the other side of that burn / or the signs of it being blow off on the other side.

Edit: looks like there are 2 optocouplers like 1/2" down from the burn mark, so there probably wasnt one where the burn mark is. But after viewing your pictures up close, it looks like your burned the crap out of the board where you replaced the 2 capacitors right next to each other about 1 inch from the burn mark. So it could very well be that you soldered it badly, youll get better with practice. Hopefully you didnt use plumbing solder though and one of those plumbing irons that creates a huge spark between two probes and is like >80w?