Sceptre X22WG-1080P (different board than on other threads)

[Skoffer]

I've got this monitor that is having backlight issues. I have replaced all of the capacitors with low ESR caps purchased from right here at BadCaps.

That didn't solve the problem, so I ordered new CCFL bulbs from CCFLWarehouse and replaced them. The reason I did this was I found out through testing with some other backlights that I have free, from a 19" monitor, that they light up and stay lit just fine.

So, I have taken the old lights out and soldered the new ones into place. Here is where I think I did something wrong, though. Because I am still having the 2 seconds to black problem with the new bulbs.

I have taken them out and inspected and resoldered the wires, but still no luck. I am, admittedly inexperienced with soldering wires together. I am well practiced with circuit boards, though.

I suspect it is still my crappy solder job on the wires. So, my question to you guys is, how do I go about ensuring that my solder joints from the wire to the bulb is good? And, is it possible, that there is still something wrong with the board, and it is having trouble lighting the larger bulbs compared to the test bulbs from the 19" monitor?

[retiredcaps]

Re: Sceptre X22WG-1080P (different board than on other threads)

I suspect it is still my crappy solder job on the wires. So, my question to you guys is, how do I go about ensuring that my solder joints from the wire to the bulb is good?

Use your multimeter to make sure there the solder joint is good. I suspect it should read less than 1.0 ohms.

A lamp soldering tutorial is at

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

[sabre504]

Re: Sceptre X22WG-1080P (different board than on other threads)

Also test the secondary windings on the transformer ,
It may have enough in it to light 19's but maybe not for the 22's.
If you have already done so ignore me but it will rule it out as a cause.

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

Thanks for you help so far, guys.

I don't know much about transformers, but below are the results I got from testing the pins.

Here are my results on the transformer:
1 to 2 - 1.0 ohm
1 to 3 - 1.0 ohm
1 to 4 - 1.0 ohm
1 to 5 - 1.0 ohm
2 to 3 - 1.0 ohm
2 to 4 - 1.0 ohm
2 to 5 - 1.0 ohm
2 to 6 - 1.0 ohm
3 to 4 - 1.0 ohm
3 to 5 - 1.0 ohm
3 to 6 - 1.0 ohm
4 to 5 - 1.0 ohm
4 to 6 - 1.0 ohm
5 to 6 - 1.0 ohm


1 to 2 - 1.5 ohm
1 to 3 - ~150k ohm
1 to 4 - ~150k ohm
2 to 3 - ~150k ohm
2 to 4 - ~150k ohm
3 to 4 - 1.0 ohm


based on the sticky guide, I'm guessing there may be a problem here.

You can see my numbering in the attachment.

[sabre504]

Re: Sceptre X22WG-1080P (different board than on other threads)

Hi sorry i meant the inverter transformer
See pic i have ringed each end flip the board over and measure the resitance between the 2 pins in the red area and do the same in the yellow area and post result

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

Hi sorry i meant the inverter transformer
See pic i have ringed each end flip the board over and measure the resitance between the 2 pins in the red area and do the same in the yellow area and post result

I got 645 ohm across both sets.

btw, I updated the values for the other transformer. I wasn't using a high enough setting on multimeter.

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

Use your multimeter to make sure there the solder joint is good. I suspect it should read less than 1.0 ohms.

A lamp soldering tutorial is at

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

I got exactly 1 ohm on each light. I actually used that same guide as a reference before I started.
I tested the 19" bulbs and got the same reading. I think my solder joints are good.

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

I got 645 ohm across both sets.

Do those values seem right?

[selldoor]

Re: Sceptre X22WG-1080P (different board than on other threads)

Do those values seem right?

If within 3% of each other they should be ok
Is there a part number on them.

Please can you update your profile with country and mains voltage

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

If within 3% of each other they should be ok
Is there a part number on them.

Please can you update your profile with country and mains voltage

Done.
The only numbers I see on the Inverter transformer is LTL22000703U and 0734C6. You can see those numbers in my original attached pic.

What should I try next? I plugged the 22" lights in to the 19" monitor, and all 4 lights light up, temporarily, but they suffer the 2 seconds to black on that monitor, also. I kinda assumed the 19" just couldn't push enough voltage to keep them lit.

What would be my next steps, here? If the transformer is good, all the caps have been replaced, and the backlights are brand new, what else could be wrong? This is the most work I have ever had to do to resurrect a monitor. Actually, I should say, this is the most work I've been willing to do to resurrect a monitor. This one is for my own personal use, so I kinda want it to work, again.

[selldoor]

Re: Sceptre X22WG-1080P (different board than on other threads)

Can you try the 19in bulbs plugged into the 22in board?

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

Can you try the 19in bulbs plugged into the 22in board?

Yes, I've done that. They stay on.

I have another 22" monitor, working, and I think I am going to pull the ccfls out of it and see if the work, then try these news ccfls in it.

I'll report back once I'm done.

[selldoor]

Re: Sceptre X22WG-1080P (different board than on other threads)

I have been looking at the back board pic there seems to be browning around
U1 but not on U2 - what are the part numbers - perhaps test them.

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

I have been looking at the back board pic there seems to be browning around
U1 but not on U2 - what are the part numbers - perhaps test them.

4511GH
626696

Those are the numbers as read off of U2. The numbers on U1 are the same, but distorted, maybe by heat damage.

That browning in the picture, though is not as visible with the naked eye. I had to get it in the light at just the right angle to see it, but it is definately present around U1 and not U2. U1, to my untrained eye, looks to show presence of heat damage.

These are ICs, correct? How do I test them?
EDIT - nevermind...they are mosfets.

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

Ok, well, it is definately the new ccfls causing the issue. either the bulbs themselves or my soldering job is still weak.

The Sceptre x22WG-1080P is now working with the ccfls from the other monitor, which happens to be an Acer AL2216w. Funny thing is, the Acer seems to have a little more tolerant hardware than the Sceptre, because the acer is staying lit with the new ccfls. It is making a slight buzzing sound when the brightness is dimmer than about 60%, though. But above that, and it is fine.

Anyway, thank you all for your advice and help. I'm going to be content with what I have for the moment and hope it lasts.

[Lumberjack777]

Re: Sceptre X22WG-1080P (different board than on other threads)

It sounds like a soldering problem with the CCFL's. Though it could be a defective bulb. Sometimes that silicone cap on the end can be ripped, or even pull the wire off a little when you slide it back on; if the soldering is not solid.
Two things to remember when replacing ccfl's.
1. You can always use silicone caulk to fill any tears or rips in the end caps; to prevent internal shorts.
2. You can always test the lamps before you reinstall them inside the lcd screen assembly. In fact you should. That way if there is a problem you won't have to disassemble the entire lcd screen again. ~L-J-7~

[Skoffer]

Re: Sceptre X22WG-1080P (different board than on other threads)

It sounds like a soldering problem with the CCFL's. Though it could be a defective bulb. Sometimes that silicone cap on the end can be ripped, or even pull the wire off a little when you slide it back on; if the soldering is not solid.
Two things to remember when replacing ccfl's.
1. You can always use silicone caulk to fill any tears or rips in the end caps; to prevent internal shorts.
2. You can always test the lamps before you reinstall them inside the lcd screen assembly. In fact you should. That way if there is a problem you won't have to disassemble the entire lcd screen again. ~L-J-7~

Thank you for this. It looks like my problem was with the silicon caps, and also with not having the spacers between the bulbs. That was what was causing my vibrations, and turns out was probably also causing the bulbs to short out against each other. I used shrink tubing over my solder joints, and then used a small amount of silicon in about 5 places to secure the bulbs together.

The monitor is purring like a kitten, now...figuratively. It isn't making any noise whatsoever.

Just thought I would post this as the solution for this issue, in case anyone else might have some problems. I'm now sporting dual 22" monitors that I paid a total of about $32 for. The $32 was the cost for the ccfls and the few capacitors that I replaced.

[Lumberjack777]

Re: Sceptre X22WG-1080P (different board than on other threads)

Thanks for the update and resolution. I learned about that the hard way. I used to just shove it all together and tuck it back in and "hope". After a couple problems like you had I learned to make sure everything was soldered properly and insulated before tucking it all back in.
Congratulations on your ccfl replacement! That is generally one of the toughest repairs on an lcd monitor.