Nichicon HM, HN and HZ are discontinued. Use HD and HE...
Panasonic FM and FR are low esr...
United Chemi Con has also KY and KZE series ...
Rubycon has ... ZL* series.. ZLK , ZLG
Guess it pays to keep up with these things, huh?
Avoid KZG and KZJ series from them, they're known in the repair guys "circle" for going bad with no reason after some time, probably manufacturing flaw in these series.
I thought they fixed them? The problem batches had date codes of, IIRC, 2004 (maybe as late as 2006?).
Nev, the video posted is really blurry and moving, making it hard to see who's made the caps (and series) so we can better match them up. If you can post any close-up pics of the caps, or just jot down the markings, that'd help.
About the only cap you need to worry about discharging is that big mother with the tie strap around the middle. This filters the incoming mains (240V?) before it gets sent to the switcher primary. Since this is 50/100Hz, it can be any GP cap, and it's rare this goes bad (good news!). This cap also handles about 340V after rectifying (bad news!). So, if you discharge only one cap, it'll be that one. A simple way of doing this is to bridge the leads of the cap with a resistor. The higher the value of resistor, the lower the power rating can be (and the longer it takes to discharge). I just check with a meter to see if it needs to be discharged, and if it does, I have a few various high-wattage resistors handy. As canuck mentioned, I've also never had to discharge a modern monitor PSU - they seem to have built-in "bleeder" resistors/circuitry. I'd still measure that big cap, though...
The eBay seller has posted pics of what appear to be UCC KZE series caps (good!). If that is, in fact, what he/she actually sends you, then go ahead and take the gamble. The last link shows what appear to be the newer Panasonic FR series by the color and font, but no mention of series is given. If this seller seems legit, go for it, but don't be surprised if what you open up is some other brand or Chinese counterfeit.
Now, while I agree about the PSU problem being cap related, mariush does bring up a very good point. If you're not sure of what to replace, or how to test, then the best bet is to replace any/everything that would cause this problem. Since you're not blowing fuses, the primary can be declared good. Since the light comes on and gives an attempt to power-up, then we can assume the 5Vsb is good, too. Most monitors now incorporate a "soft start" feature in the main control chip to keep the initial surge of current to a non-fuse-blowing level when it has to charge up the output caps. To do this it uses - you guessed it - a capacitor. In your video, it should be the little guy to the left of the main filter cap with the strap,
right next to the big heatsink! Since that little cap only adds about another 25 or 30 cents to the order, may as well swap it out while you're in there.
Since I see that some of those caps are butting against each other, it is imperative that you double-check the diameter, lead spacing, and height of the new caps to match the old ones. I accidentally jotted down the wrong diameter for some mobo caps and had to re-order. It was a difference of 8mm vs. 10mm. I still have no idea how I wrote down "10" when the calipers read "8".
Another common failure is the inverter (backlight driver) caps/transformer(s). This is where the HV for the CCFLs is generated. Again, if you're not sure, just replace the caps you find in there. Since all this is on the same PSU board, you may as well do it while you're there. The transformers/CCFLs would be the next thing I'd check if recapping doesn't work. For now, we'll just take it one step at a time.
Lastly, a real noob would
still be trying to get this thing open. You've done that, taken the holiday movie, and have a relatively good understanding of what needs to be done. Just take good notes, make sure the caps are the right way 'round, check for soldering errors, and as your fellow countryman once advised: "Don't Panic!"
nop
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