Asus k52f baclight not working?

[Apocalypso]

Hi,

friend of mine has a problem with his Asus K52F laptop, screen stays black but the matrix is working, I mean there is an image on the screen but it is very dim so I guess that there is a problem with the backlight?

I read somewhere something about power inverter but this is LED LCD and it does NOT use an inverteror maybe I am wrong?

Any hint is more than welcome...

thanks in advance,
Teo

 

[getochkn]

something with the power to the led's then. could be a loose cable, could be whatever powers led backlight displays. I haven't had any like that come into my shop yet, just old tube lit ones with an inverter, so I'm not sure other than bringing it to a laptop tech who can diagnose it and test the led power for voltage, etc, which is where I would start at.

 

[Brett928S2]

Hi

We have done a fair few in my repair shops of LED screens....

Its ALWAYS new screen time.... customers ALWAYS hope it the cable , but it never is lol..

But yes that's good advice... laptop repair shop for diagnosis...

All the best Brett

 

[getochkn]

So is the LED power mech usually in the screen then brett? Like I said, never had one come in yet, just done tonnes of older ones and it's either invertor or have to reflow the board for no video.

 

[Apocalypso]

First of all 10Q 4 the surprisingly fast response, I really appreciate it!

So there is no hope But from other hand it doesn't works and basically I have nothing to loose so I'll try to determinate where is led power source and whats wrong.

Will keep U informed however,

Thanks once again and apologize 4 my English, it is not even my 2nd but 3rd language

Teo

 

[Apocalypso]

Just to add that screen is LP156WH2(TL)(EA)....

 

[Apocalypso]

I did some measurements and found that there is a 12V DC on the spot near the led connector (marked on the picture below) but on the board it is marked as 32V so I'm just curious if it is OK or this could be the problem?

Also, is it possible that hinge switch is broken; I'm talking about switch that turns off screen when the laptop is closed?

http/img521.imageshack.us/img521/582/img4660eh.jpg

 

[Apocalypso]

Another photo, I just found another interesting chk point named as BL_ON and if I am right I should measure 3,5-5v here if the the lid closing switch is working properly?

http/img9.imageshack.us/img9/9329/img4662c.jpg

 

[Apocalypso]

I did one more test, I changed the closing the lid action to shutdown and than try to close the lid ans nothing happens... So I guess the switch (magnet) is not working?

 

[Apocalypso]

...and the problem is...

http/img26.imageshack.us/img26/5719/img4667d.jpg

.. ...'switch'

http/img534.imageshack.us/img534/4615/img4662l.jpg

It works now

 

[getochkn]

Very nice. So did you switch the "switch" or just bypass it?

 

[Apocalypso]

I though I'll need to either desolder it or make a shortcut (wasn't sure if switch is in a closed or an open state by default) but than I notice it's possible to simply unplug complete module which I did it and now everything works fine except I loose the close-lid functionality.....

By the way, is it possible to order this module somewhere? I'm also having lot of problems with the touchpad right click, sometimes work sometimes doesn't, so I also need a new button but don't know where I can find i the right one?

Anyway, thx again to all of U; I hope this thread could be helpful to someone else with same or similar problems....

 

[Martin72]

Can you tell me where I can find this switch?

I though I'll need to either desolder it or make a shortcut (wasn't sure if switch is in a closed or an open state by default) but than I notice it's possible to simply unplug complete module which I did it and now everything works fine except I loose the close-lid functionality.....

By the way, is it possible to order this module somewhere? I'm also having lot of problems with the touchpad right click, sometimes work sometimes doesn't, so I also need a new button but don't know where I can find i the right one?

Anyway, thx again to all of U; I hope this thread could be helpful to someone else with same or similar problems....