ASUS VH222 23" LCD screen. Powers on, but has no image. Tried the flash light trick and saw faint image. So either inverter is bad or back light is bad. I'm suspecting the inverter because there's a discoloration spot on the power board. Please take a look at the picture with the voltage reading. Any help will be appreciated!
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ASUS VH222 has no image
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Re: ASUS VH222 has no image
If you look at the screen in the dark room, do you see the backlights flash on for seconds?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
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Re: ASUS VH222 has no image
Originally posted by newtothis View PostCan you take a pic of the connector that goes to the logic board so we can see the silk print please.
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Re: ASUS VH222 has no image
Originally posted by budm View PostIf you look at the screen in the dark room, do you see the backlights flash on for seconds?Last edited by ucdzombie; 12-04-2013, 02:22 AM.
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Re: ASUS VH222 has no image
Could easily be the inverter transformer.
Can you see the numbers on it?
May be one of these?
http://www.lcdparts.net/TransformerD...ProductID=3699
To test - no power to board meter on ohms 2000 test S1 to S2 and S3 to S4Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740
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Re: ASUS VH222 has no image
Originally posted by selldoor View PostCould easily be the inverter transformer.
Can you see the numbers on it?
May be one of these?
http://www.lcdparts.net/TransformerD...ProductID=3699
To test - no power to board meter on ohms 2000 test S1 to S2 and S3 to S4
S1 to S2 has 500 ohms, S3 to S4 has no reading at all. I didn't de-solde the transformer. I tested by touching the leads on the back of the board. Did I do it correctly?
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Re: ASUS VH222 has no image
Originally posted by ucdzombie View PostI don't remember seeing it flash at all. When it turns on, there's no back light because the color of the screen doesn't change to dark bluish grey. I will check again today.
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Re: ASUS VH222 has no image
Originally posted by budm View PostIf you look at the screen in the dark room, do you see the backlights flash on for seconds?
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Re: ASUS VH222 has no image
OK, then check the transformer high voltage windings resistance, you can have bad lamps also, you may have get a couple test lamps or make some otherwise you can spend a lot of time trying to fix the board when you may have lamps problem, need to narrow that down.
https://www.badcaps.net/forum/showth...er+testing+cflNever 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
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Re: ASUS VH222 has no image
budm - looks like his inverter transformer is shot - if he is testing it correctly.
500 ohms and 000 ohms!! post 7
ucdzombie - we really need the part number off the transformer but it doesnt
look good.
If you cant read the number (even parts of it might help)
then a picture of the back of the board where the transformer is so we can see where you measured. Sometimes there is lacquer on the joints try again
making sure you are down to metal.Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740
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Re: ASUS VH222 has no image
Sorry, I missed that post.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
Comment
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Re: ASUS VH222 has no image
Originally posted by selldoor View Postbudm - looks like his inverter transformer is shot - if he is testing it correctly.
500 ohms and 000 ohms!! post 7
ucdzombie - we really need the part number off the transformer but it doesnt
look good.
If you cant read the number (even parts of it might help)
then a picture of the back of the board where the transformer is so we can see where you measured. Sometimes there is lacquer on the joints try again
making sure you are down to metal.
http://www.ebay.com/itm/Inverter-Tra...-/261267004394
And the back of the board:
Also, remember I said that there's a discoloration spot on the board where those two Zeners are. They're weird. One side has 15v and the other side has 0v (as shown in the first post).
Thank you everyone for being so supportive!!!Last edited by ucdzombie; 12-05-2013, 12:49 AM.
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Re: ASUS VH222 has no image
Remove it and test again check the winding is not snapped just by the pin - if it is it may be re-attached
I would get one ordered from the link you have found.
I dont know about the zeners -perhaps they just run hot - budm would know better.
Perhaps upgrade any caps associated will help them run cooler.Last edited by selldoor; 12-05-2013, 06:35 AM.Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740
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Re: ASUS VH222 has no image
Originally posted by selldoor View PostRemove it and test again check the winding is not snapped just by the pin - if it is it may be re-attached
I would get one ordered from the link you have found.
I dont know about the zeners -perhaps they just run hot - budm would know better.
Perhaps upgrade any caps associated will help them run cooler.
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Re: ASUS VH222 has no image
Originally posted by Davi.p View PostThe not turning on of the backlights and the lack of a voltage on that ferrite seems to me a strange behavior for a normal transformer or ccfl failure, can you post a picture of the downside, 'cause is needed to watch at wich point to test for the psu outs.
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Re: ASUS VH222 has no image
WoW! not seen one do that before - if you can find the end of the wire, you can try and fix it. To solder you will need to scrape the laquer insulation off the end of the wire. before you move on to making a pin test the resistance again it needs to be within 3 % of the other one so 485 to 515ohms if the s1 to s2 is correct..Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740
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Re: ASUS VH222 has no image
The wire will be hair thin, it is going to be difficult job since the wire will be too short to reach the post.
You will also have to remove the carbonized section of the board since carbon conducts electricity especially it is in the high voltage section that can be as high as 1500V or more.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
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