Author Topic: hp monitor 1740  (Read 2933 times)

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Offline kjn4685Topic starter

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hp monitor 1740
« on: July 31, 2014, 10:56:12 pm »
I have a hp monitor that goes off after a second or two. I've changed all the caps and diodes. Now I am changing the ccfls. I have tested all the voltages and anything that I can test. Does anybody have any ideas.
 s/n cnc63710j9.
 

Offline hobo2566

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Re: hp monitor 1740
« Reply #1 on: August 01, 2014, 11:45:40 pm »
If your power bard looks like one in attached image, first check if transistors circled in red are OK (5706 or 5707 in most cases), if not check other components circled in green.

In most cases flickering on/off is caused by shorted transistor.
 

Online wraper

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Re: hp monitor 1740
« Reply #2 on: August 02, 2014, 12:49:06 am »
Check secondary windings of the transformer(s), should have something around 1k resistance and less than 5% difference between them.
 

Online wraper

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Re: hp monitor 1740
« Reply #3 on: August 02, 2014, 12:54:55 am »
If all capacitors are already exchanged and secondary windings are ok, 95% that one ccfl is dead and protection kicks in because of that.
 

Offline Khaveer

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Re: hp monitor 1740
« Reply #4 on: August 22, 2014, 09:44:43 am »
Is it only the backlight that turns itself off? I have a hp l1940t that had the same fault. I couldn't figure out what was causing the problem so I ended up disabling the overload protection hoping that without it the faulty part will simply release the magic smoke but it didn't. I've been using the monitor for a year and it's still ok. If I recall correctly I had to short a cap to disable the protection, so if you won't be able to find the fault I can take my monitor apart and check it.
 

Offline kjn4685Topic starter

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Re: hp monitor 1740
« Reply #5 on: August 22, 2014, 07:37:09 pm »
I appreciate everybody that contributed to this post. I have it by changing the girls.
Again I thank everybody .
Lou
 

Offline JoeO

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Re: hp monitor 1740
« Reply #6 on: August 22, 2014, 09:12:38 pm »
I appreciate everybody that contributed to this post. I have it by changing the girls.
Again I thank everybody .
Lou
Women were pressing the power off button?
The day Al Gore was born there were 7,000 polar bears on Earth.
Today, only 26,000 remain.
 

Offline kjn4685Topic starter

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Re: hp monitor 1740
« Reply #7 on: August 25, 2014, 06:40:38 pm »
I did not preview the post before I sent it. Sorry I meant I changed the ccfls not girls.
Again I am sorry.I just what to let everybody know that it is fixed.
Thank everybody that gave me advice
Lou
« Last Edit: September 05, 2014, 11:21:23 pm by kjn4685 »
 


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