Proview PL926Wbi - recapped, same shut off issue

[Lumberjack777]

Re: Proview PL926Wbi - recapped, same shut off issue

Ok I now know what bulbs are bad. On the 1st monitor, the one this thread is about, I definitely know 1 that is really bad. (Made the 2nd monitor screech and fritz), and am a little suspicious of a 2nd bulb on the first monitor. I know which bulb is bad on the 2nd monitor. OK! Small steps to success. (little happy dance)

Ok sensei, now what?

Ok good. You've narrowed it down to the ccfl. A place a lot of people out here recommend is CCFL Warehouse http://www.ccflwarehouse.com/

Hopefully its just a bad wire connection. Then you won't have to buy anything.

You'll need to strip it down to just the LCD panel. Then the outside edge pieces unlock and pry loose. Sometimes little screws have to come out in places. Be very careful with the board that connects to the plastic that goes inside the lcd screen.
You'll pry off a plastic piece around the edge (normally) and the lcd screen will be loose. Don't let it drop out. Then you'll get to some plastic sheets (diffuser sheets). Make sure those stay in the exact same order for reassembly. Then to the thick plastic plexiglass. The ccfls will be on the top and bottom. You may have to pull it out a little to release the bulbs.
Then you need to pry the end cap off the bad bulbs. Check for broken wires here. It might just be a bad soldering connection. If the bulb(s) are cracked or bad you'll have to order some new one(s). You'll need to measure the length and the diameter of the ccfl and put that in your order from ccfl warehouse. http://www.ccflwarehouse.com/tutorials.html
You can also call them and talk to them and maybe they can help with the measurements.
Just follow those tutorials I just posted. Then you put it all back together again carefully.
You want to perform this in a dust free room with no pet hair also. Anything that could stick to the plastic diffuser sheets.
The best thing is to go slow. Take your time. Good luck grasshopper.

[Lumberjack777]

Re: Proview PL926Wbi - recapped, same shut off issue

There is another option you could use, that I have never shared with this forum.
I sometimes do repairs for people and I get a bad ccfl. When I tell them the amount I'll need to charge to replace a single lamp, they would rather junk the monitor and buy a new one. So I give them this option instead.
I take a ccfl that I have leftover. And I plug it into the connector with the bad bulb. Then I find a spot on the lcd panel that is flat and will fit the bulb, and I tape it down. And cover it with duct tape. The entire length of the bulb. By having the 4th lamp lit the monitor now stays on full time.
The lamp used can be a little smaller. And you can often find them at a local electronics recycling center for a few bucks. Or taken from a scrap lcd monitor.
Three bulbs is usually plenty of light for the monitor to be useful. And the diffusing technology of the plastic distributes the the light fairly evenly over the entire lcd screen.

[Wyld_Goose]

Re: Proview PL926Wbi - recapped, same shut off issue

Thank you. I'm now wondering what is going to be more difficult. Checking/Changing out CCFL tubes for the first time, or finding somewhere in my house without dog hair. lol

Again. Thanks. I will attempt to keep updated on success or failure.

[Wyld_Goose]

Re: Proview PL926Wbi - recapped, same shut off issue

What I have learned:
LCD panel corners are easy to crack when the light goes out in the workshop just as your separating the screen case, an you attempt to set it back down carefully, and the corner just catches the edge of the case and doesn't want to support the weight of the entire panel. Needless to say the original monitor I've been working on here is screwed.
Dunno about replacing an LCD panel or if it's even worth it.

I've learned the working with CCFLs sucks! I turned to working on the 2nd monitor and figured at this point, where I was going to buy new CCFLs I needed to replace in both of them, I might as well use good bulbs from the first monitor to get the second one working.

I successfully took a good bulb from the first and replaced the bad bulb in the 2nd. Not fun.

So in researching CCFLs, it seems just like with some of the bad caps out there, it's not a matter of if, but when CCFLs start to die. And when they do start to die they tend to draw more voltage in from the inverter and can tear it up bad, especially if there are crappy caps on it.

I had two thoughts on this. One being a question of: Would it not be smart to replace all caps with a slightly higher voltage ratings, knowing that CCFLs will start to die within 2-4 years?
And the second, because CCFLs will die, would it not be better if your going for a new monitor to just bite the dollar bullet, and go LED? Seems like the extra cost will pay for itself in the long run.

[retiredcaps]

Re: Proview PL926Wbi - recapped, same shut off issue

I take a ccfl that I have leftover. And I plug it into the connector with the bad bulb. Then I find a spot on the lcd panel that is flat and will fit the bulb, and I tape it down. And cover it with duct tape. The entire length of the bulb. By having the 4th lamp lit the monitor now stays on full time.

Hmm, interesting idea.

We have seen some members try to fool the inverter pwm with a capacitor, resistor and other components, but never the above.

[selldoor]

Re: Proview PL926Wbi - recapped, same shut off issue

Dunno about replacing an LCD panel or if it's even worth it.

Probably not unless you can pick a working one up cheap where the
set has another problem.

I might as well use good bulbs from the first monitor to get the second one working.

Good Plan

I successfully took a good bulb from the first and replaced the bad bulb in the 2nd. Not fun.

Well done - so does that mean the second set is working correctly?

So in researching CCFLs, it seems just like with some of the bad caps out there, it's not a matter of if, but when CCFLs start to die. And when they do start to die they tend to draw more voltage in from the inverter and can tear it up bad, especially if there are crappy caps on it.
I had two thoughts on this. One being a question of: Would it not be smart to replace all caps with a slightly higher voltage ratings, knowing that CCFLs will start to die within 2-4 years?

Bulbs do have a life span seems to vary from 10000 hours to 20000.
Replacing the caps on the inverter board with higher voltage may give a cleaner supply and give them a longer life.

And the second, because CCFLs will die, would it not be better if your going for a new monitor to just bite the dollar bullet, and go LED? Seems like the extra cost will pay for itself in the long run.

Yes and No - seems a good idea but what is the life span of a led?
I still dont think that it is proven and the cynic in me suggests monitor manufacturers are not working to give you a set that will last any longer.
We have seen a few cases on here where LED sets go wrong and we have been unable to bottom out what the problem was.

Tough luck on Monitor 1

[Wyld_Goose]

Re: Proview PL926Wbi - recapped, same shut off issue

Well done - so does that mean the second set is working correctly?

Yup, powers up and is as good as gold. Funny how in both cases, it was the bulbs and not the caps. (not that changing them out for good ones didn't hurt) I just want my old fashion monitor powered by a hamster and wheel. Wheels needed a little WD-40 and hampsters just needed to be fed, and were cheaply replaced if they died.