AOC Envision L19W861 failure

[mrfixit01]

Re: AOC Envision L19W861 failure

Post #8? What did you get for ohms measurements on the inverter secondary transformers?

Lol. Guess I missed that one. Sorry. Which one is the secondary transformer(s) or which terminals should I test? Power off I guess? Thanks.

[retiredcaps]

Re: AOC Envision L19W861 failure

We need a clear focused picture on the backside of the power/inverter board. Yes, measure the resistance with power off and lcd unplugged.

The secondary inverter transformer pins are the ones "leading to" or connecting to the blue high voltage caps.

[mrfixit01]

Re: AOC Envision L19W861 failure

Lol. Guess I missed that one. Sorry. Which one is the secondary transformer(s) or which terminals should I test? Power off I guess? Thanks.

I see now it is 801, the one to the left center side of the board. Which terminals should I test? Do I ground one probe and test all of them? Sorry for being so slow. Trying to do a million things here. I appreciate all your help, just please be patient with me. I'm just trying to help out some other people with this and not charging anything for the work.
Your previous post just showed up after I posted this one. I see it now. Will do tonight and report back here asap. Thanks.

[mrfixit01]

Re: AOC Envision L19W861 failure

We need a clear focused picture on the backside of the power/inverter board. Yes, measure the resistance with power off and lcd unplugged.

The secondary inverter transformer pins are the ones "leading to" or connecting to the blue high voltage caps.

Here is a close up of the backside of the board. Measured resistance across terminals 8 & 9 displayed .45 m/ohms. I also tried to measure across the two blue caps but received no readings on any setting of my meter. However, I also found another flat panel lcd with similar ccfl plugs so I tried plugging it in to the AOC Envision. The display came up with my desktop and stayed on for several minutes.

[alexanna]

Re: AOC Envision L19W861 failure

If the display stayed on for several minutes,You Fixed it.
Or almost

[mrfixit01]

Re: AOC Envision L19W861 failure

This appears to be a case of 'two seconds to black'. You can verify this by hooking up a source with audio and video, stepping through the inputs, and verifying that sound remains after the backlights go away. You test verified that the backlights are shutting down, they are not being shut down by the signal card.

If you have another monitor with 4 good CCFLs with compatible connectors, try hooking up all four. If they stay on, the problem is the CCFLs in this monitor.

PlainBill

I found another lcd that had similar connectors and switched displays (even though they are different sizes) and the new display came up with a normal, if incorrectly sized, display. Reading across the power inverter showed .45 m/ohms. I could not attach an audio source with what I have available.

[mrfixit01]

Re: AOC Envision L19W861 failure

If the display stayed on for several minutes,You Fixed it.
Or almost

Yeah, except the other lcd is the wrong size and belongs to a currently operating system. PlainBill said earlier that it may indicate bad ccfl's. I'm waiting to hear more. Thanks.

[alexanna]

Re: AOC Envision L19W861 failure

If your test display stays on,you have Confirmed that the CCFLs are causing your 2 sec. to black problem.

[mrfixit01]

Re: AOC Envision L19W861 failure

If your test display stays on,you have Confirmed that the CCFLs are causing your 2 sec. to black problem.

Thanks, that's what I was afraid of. I'm checking wiring now to see if something could have been shorted or cut. Next I'll have to find a CCFL supplier that doesn't cost an arm/leg or gallon of gas! Never did this sort of repair before. It's great knowing what to do now.

[alexanna]

Re: AOC Envision L19W861 failure

After thinking on how the monitor was used most likley 24/7 i would think it would be something other than a wire problem.
there several CCFl suppliers that members have good luck using.

[PlainBill]

Re: AOC Envision L19W861 failure

Yeah, except the other lcd is the wrong size and belongs to a currently operating system. PlainBill said earlier that it may indicate bad ccfl's. I'm waiting to hear more. Thanks.

As Alexanna said, you have identified the problem. If I recall correcctly, CCFL Warehouse has good reviews from members here. I suggest you wait until retiredcaps chimes in to confirm that. He probably also has a link to a video on replacing the CCFLs. It is NOT a job for someone with a surplus of left hands like me.

PlainBill

[alexanna]

Re: AOC Envision L19W861 failure

If someone like me,[I use to try to put the square pegs in the round holes]anyone can do it
Just take your time, be very careful with the ribbons on the panel. There are some that have a bead of silicone holding the LCD to the framework. Do not force anything.
CCFl warehouse has been very helpful to make sure I get the right parts.
There phone support is very good, and they like talking to you.Retiredcaps dose have some other vendors that are good.

[mrfixit01]

Re: AOC Envision L19W861 failure

As Alexanna said, you have identified the problem. If I recall correcctly, CCFL Warehouse has good reviews from members here. I suggest you wait until retiredcaps chimes in to confirm that. He probably also has a link to a video on replacing the CCFLs. It is NOT a job for someone with a surplus of left hands like me.

PlainBill

You've got that right. I spent the better part of the day just trying to figure out how to take the display apart. I finally got one side out and both tubes are blackened at each end. One is actually cracked. These look like special tubes. They are mated into a channel with fitted ends and glued together. I've sent a request to CCFL Warehouse with the measurements and am waiting for a reply, probably by Monday.

(I'm getting my second wind. Next I have a 27" Sharp tv that powers off at random times. We haven't been able to use it in a year +)

[retiredcaps]

Re: AOC Envision L19W861 failure

Tutorial on taking apart and putting together the ccfls, which you may have already seen, is at

http://www.ccflwarehouse.com/lasotu.html

[PlainBill]

Re: AOC Envision L19W861 failure

You've got that right. I spent the better part of the day just trying to figure out how to take the display apart. I finally got one side out and both tubes are blackened at each end. One is actually cracked. These look like special tubes. They are mated into a channel with fitted ends and glued together. I've sent a request to CCFL Warehouse with the measurements and am waiting for a reply, probably by Monday.

(I'm getting my second wind. Next I have a 27" Sharp tv that powers off at random times. We haven't been able to use it in a year +)

Good, good. By summer you'll be working on 50" plasmas and repairing iPods.

PlainBill

[mrfixit01]

Re: AOC Envision L19W861 failure

Tutorial on taking apart and putting together the ccfls, which you may have already seen, is at

http://www.ccflwarehouse.com/lasotu.html

No, I haven't fallen off the face of the Earth, yet. I have been waiting for money to purchase the ccfl's to repair the AOC Envision tv. Just arrived today and will install them all this weekend. Only cost $43 for 4 lamps, end caps, spacers, shrink tubing, replacement tapes and shipping. Thanks for the suggestion. Cross your fingers for me! More later...

[retiredcaps]

Re: AOC Envision L19W861 failure

Only cost $43 for 4 lamps, end caps, spacers, shrink tubing, replacement tapes and shipping.

Go slow and take pictures so you can re-assemble. Do not force anything because the ccfls are fragile. Work when not tired and have decent light.

[mrfixit01]

Re: AOC Envision L19W861 failure

Go slow and take pictures so you can re-assemble. Do not force anything because the ccfls are fragile. Work when not tired and have decent light.

Fragile is not the word for it. I had one assembly all together and realized that I forgot the shrink tubing. So I broke one after unsoldering and adding the shrink tubing. As I went to slide it back on, the brand new ccfl broke. I went back through the used ones and picked one that looked ok. Got it all back together - without the shrink tubing. Then I started on the other set. This time I placed the shrink tubing over the wire before soldering. Good Boy! Wrong. As I got to slide the silicone end cap back over it (they are all at a 90* angle) the end wire broke. So now I've wasted that $43 plus the original $10 for the bad caps.
I will never do this again!!!!

[retiredcaps]

Re: AOC Envision L19W861 failure

So now I've wasted that $43 plus the original $10 for the bad caps.
I will never do this again!!!!

Sorry to hear about your repair. For others reading, ccflwarehouse.com also has complete LCD Monitor Backlight Assemblies to make it an easier repair.

http://www.ccflwarehouse.com/cohaccas.html

PS. You can always sell this on ebay to recoup some of your money. The power and logic board are worth something.

[mrfixit01]

Re: AOC Envision L19W861 failure

Lol. It's for a friend, not mine. I'm reusing two of the old tubes. Almost finished with the switch/resolder. Note to self: don't use shrink tubing that comes with rebuild kit. It's too thick. Once the end caps are slid over it the set won't fit into the track. On the second redo I left off the shrink tubing and had no problems. Takin' a break. We'll see if this works in a bit. I just hope the two tubes I'm reusing are good. Originally there was only one that was cracked and blackened on both ends. The circuit would not light any since the one went out.