Philips 42" Plasma TV Problems - Blue Dots Randomly Appear

[jklillibridge]

Available settings on the volt meter are:

ACV (200V or 500V)

DCV (2V, 20V, 200V, 500V)

OHM (2M, 200K, 20K, 2K, 200)

DCA (2mA, 20mA, 200mA)

and a little symbol that looks like sideways triangle with a line through it horizontally and another perpendicular line coming through the tip of the triangle

[jklillibridge]

Bigger photo

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Bigger photo

[martini161]

AC 200v is good. as for where to place them, cant really tell from the picture, my eyes are to old sorry try just following the traced out from the pots and finding a and putting hte positive on the correct side and the negative to ground

[jklillibridge]

Stupid question, but what are the "pots"? I'm guessing they are the white screws that I will turn to adjust the voltage.

Also, I have added another photo below and circled the area where I first tried to test the voltage..where all the wires come in to the slots labeled for vscan,etc. I stuck my voltage meter pins down in the correct slot until I thought they were touching copper and I got nothing, so I'm assuming that might not be the place.

Is that where I am testing the voltage? Do I need to remove anything to test the voltage?

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[Alathald]

Pot is short for potentiometer (in this case anyway ). If you're not sure what a pot is you may want to rethink doing this work yourself. If you do decide to continue neither I nor anyone else on this forum will claim any responsibility if you mess something up.

Having said that, as far as where to test you want to find a spot that is directly connected to each lead on the pots. For example, on the one pot I can kinda trace the leads from:

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[jklillibridge]

Okay, I think I understand what pots are now...it's what I thought they were.

I actually did this just a few minutes ago:

Waited for the tv to start showing blue dots...paused it. Adjusted the VSet just a slight counter-clockwise movement...and bam! Blue spots dissapeared!

Although I don't know the voltages of what everything is at right now...so I kind of want to verify that so I can make sure things look in line. Is there any danger or risk to what I just did? Should I bother checking the voltages, or should I just seal this baby back up and hang back on my wall?

Thanks to all for the help. This has been very helpful and saved me cash!

[DMB2000uk]

You should definitely make sure you check what voltage you set the TV to. You don't want to be too far out on the manufacturers specs as it could have unforeseen consequences.

Imagine if you had of turned the dial the other way

Dan

[jklillibridge]

Okay, I will try and test the voltages tonight.

I guess I am a little frightened I will short it out, which is why I want to know exactly where to place the black and red leads from the voltmeter on the board. The diagram above with the stars is a good indicator, but looking for real specific, dummy-proof instructions.

Do I basically put my red lead from my voltmeter where Alathald drew the star on the photo and then put my black lead on a ground screw?

If anyone can help guide a rookie here, that would be appreciated...and I won't hold you responsible! Promise!

[Alathald]

I just took a second look at the pic and it appears that there are some test points on the board...I've starred the Vscan, Vset and Vg points. You'll probably need to find a test point labeled "Ground" or "Gnd" and measure the voltage between the Voltage (Vsomething) test points and the Ground test point.

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[Apoptosis]

I'm glad my posting what the issue was helped someone! If you are nervous about where to put the volt meter then don't do it, not worth risking a TV. Just be sure to lower the other two voltages I mentioned a bit also.

[jklillibridge]

Great...thanks! I think I'm good now. I remember seeing those labels with mini holes in the board and wondered if those were test points. I'll look for the ground test point tonight as well and give this a shot.

One last, really stupid question. TV should have power, but should the tv itself be powered on? That is how I was doing it last night - power connected and tv turned on, but was not sure. I read some other thread about it somewhere else and it seemed like this guy was told to have power connected, but not have the tv on.

[DMB2000uk]

Well unless that circuit board has full power when the TV is on standby (which seems unlikely), then the TV will need to be on completely like it was the last time you tested.

Dan

[Alathald]

Bump for edit on my last post, just wanted to be sure you used the correct test points. Glad we could help and if you can't find a Ground then you can probably use one of the screws or a wire that connects the board to the physical metal shell of the TV if and only if the whole TV is metal. Often manufacturers ground to the case so that it acts as a Faraday Cage and helps prevent interference. But it's probably best to find the proper test points and as Apoptosis said, if you're too uncomfortable with anything then don't risk it.

[jklillibridge]

Success! I was able to test all the voltages tonight. I had my voltmeter set to DC 200V for anyone that is wondering (AC will not work).

I lowered all the voltages to the levels you listed earlier in this thread. Picture still looks good and no blue dots. TV is happily hanging on the wall again.

Problem solved. Thanks to everyone who helped out here. You guys rock.

[Apoptosis]

Awesome! If anyone else is helped by this thread please post and let us know!

[Apoptosis]

Mastercard stepped up and covered the service call and repair bill on my TV... just got the notification!

Mastercard for the win and another reason I buy things on my Mastercard!

[bubba]

sweet

[Digital Puppy]

Nice one bro!!! It's always good to have a credit card company step up with the extended warranty. For those out there considering any electronics over $1000, you might want to actively use your credit card to take advantage of any built-in extended buyer protection. Lots of time, folks want to stay away from credit cards, but if you can get this protection (and pay off the card before the interests starts kicking in) it is something that everyone should at least consider.

[vicaphit]

My parents bought my sister's first car with a credit card, and paid it off within a month just to get the bonus points!

Still, I only buy things if I have enough cash in the bank, but when your credit card company does that, you might as well buy it with credit and pay it off immediately.

[MCReighard]

I compiled the knowledge here on this forum. AMAZING! I took the base off of my TV....took out all of the many screws on the back panel...adjusted my voltages..........and BAM!!!! It's not as difficult as it seems. Use some common sense and it's as easy as pie. Blue virus is eradicated. e-mail me if you have trouble