Badcaps.net Forum
Go Back   Badcaps Forums > Electronics Theory and Troubleshooting > Troubleshooting Computer Displays
Register FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 05-06-2012, 11:07 AM   #1
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Syncmaster 2253lw inverter "not turning on"

Okay, the caps I replaced because of buldging/puffiness:
2 x 1000uF 16v by the inverters
1 x 330uF 25v
4 x 820uF 25v

The caps I didn't replace which weren't bulged/puffed up:
1 x 10uf 50v
1 x 47uf 50v
1 x 100uf 16v
1 x 100uf 450v

I know that caps that look good doesn't mean they are good and that the 100uf 450v cap has a low failure rate.

The lcd ccfl's are fine = 1000% sure of this but they are not lighting at this time.

Having said all of this by your past experiences can any of the remaining caps NOT replaced cause the lcd ccfl's not to light up?

I am ready to replace 3 of the 4 remaining for starters not replacing the 100uf 450v one - yeah watch you all say that this would be the possible culprit.

I already repaired another 22" Samsung lcd monitor which I'm using now, but this one I'm inquiring about is a tad more challeging, lol!

Any input would be greatly appreciated.

Thanks so much!

Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 11:15 AM   #2
Jasgriff
Badcaps Veteran
 
Join Date: Feb 2012
City & State: England
My Country: UK
I'm a: Knowledge Seeker
Posts: 521
Default Re: Syncmaster 2253lw inverter "not turning on"

Hi Nick,

Does the screen flick on for 2 seconds or does it not flick on at all?

And yes the other caps can still cause problems even if they are not showing bad signs as you said. I think most would eliminate that risk by swapping them.
__________________
Fixed so far : 1 Home cinema system, 16 LCD Monitors, 4 LCD TV's

How to resize your pictures guide click HERE
Retiredcaps Ideal post example click HERE
Jasgriff is offline   Reply With Quote
Old 05-06-2012, 11:16 AM   #3
retiredcaps
Badcaps Veteran
 
Join Date: Apr 2010
City & State: Canada
Posts: 8,275
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by nickt1862 View Post
The caps I didn't replace which weren't bulged/puffed up:
1 x 10uf 50v
1 x 47uf 50v
1 x 100uf 16v
1 x 100uf 450v
1) The 47uF 50V is probably your startup cap. It helps the SMPS startup properly.

2) If this was my monitor, I would have replaced the first 3 and left the big filter cap as is (100uF 450V).

3) If the backlights are not coming on and you have proper DC voltage to the inverter section, then you could have a blown fuse and/or shorted out mosfets/transistors in the inverter section.
__________________
--- begin sig file ---

If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

Please do not post inline and offsite as they slow down the loading of pages.

--- end sig file ---
retiredcaps is offline   Reply With Quote
Old 05-06-2012, 11:20 AM   #4
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by Jasgriff View Post
Hi Nick,

Does the screen flick on for 2 seconds or does it not flick on at all?

And yes the other caps can still cause problems even if they are not showing bad signs as you said. I think most would eliminate that risk by swapping them.
Jasgriff,

Nope, no flickering at all.

All the caps on this board were all chinese garbage ones except for 2 Sam Young caps which was part of the initial replacement, till I replaced the ones I mentioned with Rubycon caps ordered through badcaps.net.

Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 11:26 AM   #5
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by retiredcaps View Post
1) The 47uF 50V is probably your startup cap. It helps the SMPS startup properly.

2) If this was my monitor, I would have replaced the first 3 and left the big filter cap as is (100uF 450V).

3) If the backlights are not coming on and you have proper DC voltage to the inverter section, then you could have a blown fuse and/or shorted out mosfets/transistors in the inverter section.
retiredcaps,

Yeah replacing the rest except the 100uf 450v was my plan and it seems is what I'll do first and see what happens. Those remaining 4 are all Chinese branded garbage.

One fuse on mine is a button type 250v, T3, 15AL.
The other by the inverters is a 125v, F4, 0AL

Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 11:29 AM   #6
Jasgriff
Badcaps Veteran
 
Join Date: Feb 2012
City & State: England
My Country: UK
I'm a: Knowledge Seeker
Posts: 521
Default Re: Syncmaster 2253lw inverter "not turning on"

Are the fuses testing as open?
Jasgriff is offline   Reply With Quote
Old 05-06-2012, 11:31 AM   #7
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by Jasgriff View Post
Are the fuses testing as open?
Jasgriff,

I didn't get that far yet.


Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 11:45 AM   #8
Jasgriff
Badcaps Veteran
 
Join Date: Feb 2012
City & State: England
My Country: UK
I'm a: Knowledge Seeker
Posts: 521
Default Re: Syncmaster 2253lw inverter "not turning on"

Do you have a multimeter and know how to check them?
Jasgriff is offline   Reply With Quote
Old 05-06-2012, 12:03 PM   #9
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by Jasgriff View Post
Do you have a multimeter and know how to check them?
Setting the meter to OHMS and a good fuse should read almost zero ohms.

Most people say to take the component out to test and the probes on both leads.

Now I have to work on acquiring a multimeter.

Always wanted to get one, never got around to it or had a good enough reason to get one.

Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 12:08 PM   #10
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Deleted subpar photos - new ones in next post.

Last edited by nickt1862; 05-06-2012 at 12:46 PM.. Reason: Deleted subpar photos
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 12:45 PM   #11
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Photos of the board.
Attached Images
File Type: jpg CIMG0138.jpg (305.8 KB, 26 views)
File Type: jpg CIMG0139.jpg (279.8 KB, 24 views)
File Type: jpg CIMG0141.jpg (278.9 KB, 59 views)
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 02:28 PM   #12
Jasgriff
Badcaps Veteran
 
Join Date: Feb 2012
City & State: England
My Country: UK
I'm a: Knowledge Seeker
Posts: 521
Default Re: Syncmaster 2253lw inverter "not turning on"

Multimeter's are not that expensive to buy if you are just doing the basics.

You are right on the fuse testing however you wont need to take out the fuses to test them. Make sure that there is no power going to it whilst your checking.
Jasgriff is offline   Reply With Quote
Old 05-06-2012, 03:07 PM   #13
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by Jasgriff View Post
Multimeter's are not that expensive to buy if you are just doing the basics.

You are right on the fuse testing however you wont need to take out the fuses to test them. Make sure that there is no power going to it whilst your checking.
Thanks

nickt1862 is offline   Reply With Quote
Old 05-06-2012, 03:53 PM   #14
Jasgriff
Badcaps Veteran
 
Join Date: Feb 2012
City & State: England
My Country: UK
I'm a: Knowledge Seeker
Posts: 521
Default Re: Syncmaster 2253lw inverter "not turning on"

And Mr Retiredcaps will more than likely be along shortly to advise you on a good mulitmeter. I am sure there were some good ex military/government meterman ones that he has found before. Not sure if they are still kicking about.
Jasgriff is offline   Reply With Quote
Old 05-06-2012, 05:01 PM   #15
retiredcaps
Badcaps Veteran
 
Join Date: Apr 2010
City & State: Canada
Posts: 8,275
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by Jasgriff View Post
And Mr Retiredcaps will more than likely be along shortly to advise you on a good mulitmeter. I am sure there were some good ex military/government meterman ones that he has found before. Not sure if they are still kicking about.
The 34XR $10 deal is long dead. This was the original deal 2 months ago.

http://www.badcaps.net/forum/showpos...02&postcount=8

@nickt1862, what is your budget for a multimeter?

If you don't mind buying off ebay, this is a decent deal.

$12.47 + free shipping for a Meterman DM9B (I have the predecessor to this one)

http://www.ebay.com/itm/110642474359

The DM9B will certainly be more than adequate for troubleshooting and a good overall tool.

Last edited by retiredcaps; 05-06-2012 at 05:03 PM..
retiredcaps is offline   Reply With Quote
Old 05-06-2012, 07:31 PM   #16
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by retiredcaps View Post
The 34XR $10 deal is long dead. This was the original deal 2 months ago.

http://www.badcaps.net/forum/showpos...02&postcount=8

@nickt1862, what is your budget for a multimeter?

If you don't mind buying off ebay, this is a decent deal.

$12.47 + free shipping for a Meterman DM9B (I have the predecessor to this one)

http://www.ebay.com/itm/110642474359

The DM9B will certainly be more than adequate for troubleshooting and a good overall tool.
Thanks sooooo much for trying to help me in acquiring a multimeter.

I may have missed this (because I'm so tired right now lol!) but I don't think this is capable to also measure capacitance.

I'd be willing to spend a tad more to have that additional feature with what the DM9B already can do unless it can do this as well.

Thanks again,
Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 09:05 PM   #17
budm
Badcaps Veteran
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 12,895
Default Re: Syncmaster 2253lw inverter "not turning on"

Most DMM's with cap meter function will not be able to read large value capacitance, you should get the real cap meter with ESR function instead.
__________________
Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
budm is online now   Reply With Quote
Old 05-06-2012, 09:13 PM   #18
retiredcaps
Badcaps Veteran
 
Join Date: Apr 2010
City & State: Canada
Posts: 8,275
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by nickt1862 View Post
I may have missed this (because I'm so tired right now lol!) but I don't think this is capable to also measure capacitance.
Measuring capacitance is not as useful as being able to measure ESR (equivalent series resistance). NO multimeter can measure ESR. You need a standalone ESR meter to measure ESR. Unless you will go in the repair business, investing an ESR meter has a long payback period as they start at $65 or more. Replacing caps "blindly" costs a lot less than $65.

If the 34XR $10 deal were still active, the 34XR can measure capacitance up to 4000uF. For your purposes, the DMB9 will work fine.

The Fluke 110 series can measure capacitance up to 10,000uF, but getting one used off ebay will probably cost $75 to $100.

edit: Hmm, second thread where budm is typing faster than I am!
retiredcaps is offline   Reply With Quote
Old 05-06-2012, 09:28 PM   #19
nickt1862
Member
 
Join Date: Apr 2012
City & State: NJ
My Country: USA
I'm a: Knowledge Seeker
Posts: 23
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by budm View Post
Most DMM's with cap meter function will not be able to read large value capacitance, you should get the real cap meter with ESR function instead.
Thanks!

Quote:
Originally Posted by retiredcaps View Post
Measuring capacitance is not as useful as being able to measure ESR (equivalent series resistance). NO multimeter can measure ESR. You need a standalone ESR meter to measure ESR. Unless you will go in the repair business, investing an ESR meter has a long payback period as they start at $65 or more. Replacing caps "blindly" costs a lot less than $65.

If the 34XR $10 deal were still active, the 34XR can measure capacitance up to 4000uF. For your purposes, the DMB9 will work fine.

The Fluke 110 series can measure capacitance up to 10,000uF, but getting one used off ebay will probably cost $75 to $100.

edit: Hmm, second thread where budm is typing faster than I am!
Okay then, I shall order the DMB9.

Thanks so very much for educating me on multimeters and such as I've never used one hence the "beginner" type questions on them.



My new "problem" I'm having is finding a place that has good branded low esr 105 degree caps in these values:

2 x 10uf 50v
1 x 47uf 50v
1 x 100uf 16v
1 x 470uf 25v
2 x 1000uf 25v

Newark, Digi-key, MCM Electronics and such seem sell some which have no indication if it's low esr on any of the good brands and I only find the Chinese garbage ones that state low esr 105 degrees.

Nick
nickt1862 is offline   Reply With Quote
Old 05-06-2012, 09:33 PM   #20
retiredcaps
Badcaps Veteran
 
Join Date: Apr 2010
City & State: Canada
Posts: 8,275
Default Re: Syncmaster 2253lw inverter "not turning on"

Quote:
Originally Posted by nickt1862 View Post
I've never used one
See my fellow Canadian's 5 minute tutorial

http://www.youtube.com/watch?v=bF3OyQ3HwfU

Quote:

2 x 10uf 50v
1 x 47uf 50v
1 x 100uf 16v
1 x 470uf 25v
2 x 1000uf 25v
For each value above, go to digikey.com type the following into the search field.

10uf 50v fr

If no stock, try

10uf 50v fm

If no stock, finally try

10uf 50v fc

FR and FM are the preferred choice. If neither are available choose, FC. All are made by Panasonic and are good quality low ESR caps.

Last edited by retiredcaps; 05-06-2012 at 09:47 PM..
retiredcaps is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 06:55 PM.


Badcaps.net Technical Forums 2003 - 2014
Powered by vBulletin ®
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Did you find this forum helpful?