Riddled TV Repair Forum
Service Menu and Manual Schematics
 
   
 FAQFAQ   SearchSearch   RegisterRegister 
   Log inLog in 
Samsung UN32EH4003FXZA LED - No Backlight. But has Sound    
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair
 
Author Message
amal2004



Joined: 06 Jul 2016
Posts: 2
Location: Maryland

PostPosted: Wed Jul 06, 2016 7:27 am    Post subject: Samsung UN32EH4003FXZA LED - No Backlight. But has Sound Reply with quote

Hi. My Samsung LED TV, Model UN32EH4003FXZA doesnt have a backlight. However with flashlight, In a dark room, I can see it's working. It has sound. I already tried replacing power supply. But it didnt make any difference. Please help me to understand what's the issue here. Thank you
Google

PostPost subject: Advertisement

kuhurdler



Joined: 28 Dec 2006
Posts: 2852
Location: Overland Park, KS

PostPosted: Wed Jul 06, 2016 8:30 am    Post subject: Reply with quote

I've worked on a similar model to this one. One of the LEDs in the backlight had failed. Since the lights are in series, it takes out the whole backlight.

Poor design, in my opinion. You can replace one of the LED light strips if you can find a replacement. They were hard to find when I was looking.

You have to take the whole panel apart to get to the lights.
JTS1957



Joined: 21 Jan 2009
Posts: 2305
Location: Far, Far Away

PostPosted: Wed Jul 06, 2016 12:56 pm    Post subject: Reply with quote

Unplug each strip and apply your own power supply 20 to 25 volts DC to the strip. Observe proper polarity. IF it only contains open LEDs, the working ones will light up. IF it contains even one shorted LED, then it won't light up. In that case you can test each individual LED in the strip using your own 2 to 3 volt power supply. You may have to carefully pry off the lens to get to LED terminals.

If you decide to go with a new TV or repair this one, don't forget to decrease the back light intensity to as low as you can live with. That alone should increase the lifespan of its LEDs.
amal2004



Joined: 06 Jul 2016
Posts: 2
Location: Maryland

PostPosted: Thu Jul 07, 2016 8:50 am    Post subject: Reply with quote

Hi JTS1957, kuhurdler,
Thank you very much for your responses. kuhurdler, your correct. This is really bad design idea. Since everything else works fine, Im gonna try to fix it instead of buying new one. JTS1957, Thank you for your guidance to how to test LED strips. Since Im new to this, Im bit struggling to remove front LED panel. Anyway I hope I ll be able to fix it. Smile
kuhurdler



Joined: 28 Dec 2006
Posts: 2852
Location: Overland Park, KS

PostPosted: Fri Jul 08, 2016 7:41 am    Post subject: Reply with quote

The light strips on the one I was working on had little copper test points you could test each individual LED with a multimeter... without taking the lenses off. Not sure if they are all that way.
I used the diode function of my multimeter... the one that had failed was an open circuit.

Interestingly, my multimeter sent enough power into the LEDs to just barely illuminate them while testing them.
Google

PostPost subject: Advertisement

Display posts from previous:   
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair All times are GMT - 6 Hours
Page 1 of 1

 


Disclaimer: All information provided by RiddledTV is strictly for information purposes only. Please observe all warnings displayed on your electronic
devices. This information should only be used to help diagnose work, and all service should be performed by a qualified technician.
Contact Us       Privacy Policy       Copyright © 2015 RiddledTV.com       Advertise on RiddedTV.com