Other threads have said to replace the power board. I have removed and inspected mine and there are no visually bad caps. I tested all the wires comming out of the board all red wires show 24v when the unit is powered on and the blue has 5v. Should I look into replacing the powerboard or rebuilding it. Is there some other part that I'd be better to focus my attention to? I doubt its the backlight because I have no sound, typically when the backlight is out there is at least sound or static on the speakers, there is nothing, well other than a mocking blue power light....aaarrrrggggghhh..
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HELLO, I HAVE POLAROID MODEL 2700 and i get no blue light and nothing else. i do have 110 volts to the first board that the power cable goes to. where and what should i look for next please?
Although visual inspection shows no bad caps, this doesn't mean they're not bad. Some caps dry up inside. The Electrolytic paste is dried up. They didn't form the usual Hydrogen gas, and expand the cap, or break the seal, and push paste out.
Also, granted you are getting the proper voltages, but what are the voltages like under a load? There's no way to test this without the proper equipment.
I suggest also that it is the power board. The power supply for the monitor. If you do suspect the backlight to be out, take a flashlight, shine it at the screen, and see if you can make out any images.
I agree though that the backlight is not out, because you also have no sound.
This further convinces me that it's a power board issue.
"Everyone of the caps pulled off was still juicy inside, so they were possibly still good"?
It is with the utmost tact and diplomacy, that I ask you to Stop!
You're scaring me.
The recommended procedure for testing a capacitor, is to use a multimeter set to Ohms. Not see if it is 'Still juicy inside'. You test the Microfarad's of the capacitor, and add or subtract the Plus (+)
or Minus ( - ) percentage rate.
Electrolytic Capacitors are designed to hold a charge, then let it go all at once. Digital TV's, have capacitors that hold a Large charge! The power board has some of those capacitors.
These capacitors can hold a charge for weeks, months, or up to a year!
Should you make a circuit across the terminals, of these capacitors with your fingers, or should your fingers complete a circuit that the capacitors are in, YOU could be the recipient of that charge!
This can result in a BAD shock or a LETHAL shock!
A tech will discharge the capacitors before trying to remove them. This is a dangerous task in itself, if not done properly. Many people have tried the old fashioned way, and have melted screwdrivers. Some have pot marks on their faces, from flying molten metal coming off of the screwdriver.
When those capacitors go bad, they either dry up, or develop Hydrogen Gas inside. They're miniature Bombs!
More than Anything Else, I am concerned for Your Safety. TV's can be replaced. YOU can't!
I ask you to stop. Take it to a shop.
Yes. Now that I know your safety is not a concern, let's continue.
When an inverter is suspected of being bad, a lot of times the backlight is right behind it. Most of the time it's good to replace both. However, I realize that money doesn't grow on trees, and perhaps replacing the inverter first, then if this doesn't 'cure' the backlight problem, it's time for purchasing the backlight bulb.
I'm also of the mind, that if the power board is weak at delivering the needed amperes, then the inverter isn't going to get the full power it needs to operate correctly. Would I be fair to say, that the power board should be replaced first, then go on to the other modules, (Boards), and the Inverter/Backlight?
In my thinking, the Control Board, and the Signal Board aren't going to function as they should, if the needed power isn't there. Granted, you have the voltage, the 'speed', but you may nott have the volume.
Amperes. This is why I believe the system needs to be tested under a load, and a voltmeter won't get the reading needed. Takes an analyzer.
The CCT's used in your TV and laptops are Cold Cathode Fluorescent Lamps. Just like any fluorescent lamp, they may or may not show visual signs of failure. Testing them? I don't know the voltages for these CCFL's, do you? (Not a smart aleck answer question)
AH, here's what I've been looking for->
Polaroid Plasma TV - 2006 Models
SERVICE MANUAL
http://www.audiolabga.com/pdf/FLM3232.pd...
I would like you to download this, and use the Troubleshooting Flow Chart starting on page 15. Would appreciate hearing your findings.
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Thats what I had figured, but I thought it best to consult someone else before pulling caps. I will start by replacing them and repost with the result.
Began replacing the caps on the power board, everyone of them I pulled off was still juicy inside, so they were probably still good. Oh well, thats the game I suppose, I installed board and turned the TV on and still nothing. I held the flashlight up to the set and there is a picture there but the back light is out. I will order an inverter tomorrow and install it. There is a new problem tho, the picture that is on the board is very garbled, which board is responsible for that? The controller board or the signal board. The garbled picture looks like it could be the polaroid logo only really scrambled. Any ideas so I can order the right board at the same time as the inverter?
Thanks Joe.
Thanks for the concern, I am a very experienced electronics tinker'er. I know how capacitors work and I know what they do. I built large ones for use in rocket homing signals during my first year of electronics schooling. The caps were dismantled only after being properly removed and discharged and not with a screwdriver. In all my years of doing electronic repairs I've never seen a dried up capacitor. Plenty of blown ones. But I wanted to see if these were infact dried. They weren't. "Juicy" was just a clever way of telling you that you were wrong, without being so blunt. So, are you interested in continuing the assistance?
My goal with this repair is to not exceed the cost of a new set. $300 is my ceiling. That being said, I'll send in the power board for testing. Cheapest place I've found thus far is about $125 for testing/rebuilding. Any other suggestions? Meanwhile, is there a way to test the backlight bulbs, well I suppose them to be CCT's, individually or as a group? Is there a tell tale burn sign or break that would indicate bulb failure? The inverter board looks mint. Yes I know that doesn't mean its good. I agree that the power board should be the main focus at this point, but I had to cut down my money tree for fire wood last week, so lets rule out whatever we can to save the coin. Thanks for your help!
The chart leads me to Change the control box assembly, are they talking about the power board, signal board and tuner board as an assembly? Holy **** that'd be replacing 3 of the 5 boards in one shot...sheesh. The other result I come up with is (according to the chart) to replace the inverter. I think your first impression is where to start, I will be sending in the power board for testing and rebuilding, I will post back in a few days when I get it back. I couldn't find anyone locally that could do it in. Every shop (4) I called claimed no ability and/or interest in fixing a polaroid part. Only one asked for the whole tv and quoted a $100 diagnostic fee. No thanks. So lets begin there. In the meantime, If the CCFT's are like most out there, they run on 12v. The inverter recieves 24, and splits it 10 ways, so, a 9v battery should produce at least a dull glow on each cathode, right? I am asking before attempting, just incase you are sure it will blow it up and burn down the house and such.
After moderately reassembling the tv and testing the leads out of the inverter, the ccfts are getting no power. There is power going into the inverter but nothing comming out, but that still doesn't account for the garbled picture. Back to the drawing board....
Found an inverter for cheap, swapped it with no change. The psb is still out being rebuilt. I will post again when its back.
My rebuilt powersupply came back and when I plugged it in, it did not fix the problem. so I ordered in a new power supply. It came today. I found that the new one although it had the exact same part number has a different connector along the top. I compared the leads out and modified my wiring to fit. I powered it on and there is still NO change from before. Same black screen with a blue line pattern in the upper 1st quadrant. I went back to testing the boards and found that both boards send 24v to the inverter, and the old one sends 24v to the rest of the set whereas the new one sends 12. I am really stumped here. Not to sound helpless, but now what? I've already dumped $250 into this repair and have nothing to show for it.....AAAARRRRRGGGHhHHHh
Months later I am still at a loss, I have done some more testing and I believe the video board is out. That doesn't explain the backlight not working though, I could still use any help available on this tv if there is someone out there that knows WTH is wrong with it.
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