954,135 Members — Technology Publication meets Social Media
Username:
Password:
Lost login information?
Have something to say? Contribute New Article Reply to this Article

LCD Backlight

Hi new member, I am doing some repairs on an LCD monitor. I need to know if it is the inverter or the backlight. The screen will come on for a second and then shut off you can still extreamly dimmly see the picture. Any sugestion will be great!

blicraft
Newbie Poster
2 posts since May 2004
Reputation Points: 10
Solved Threads: 0
 

LCD backlight is merely a cold cathode florescent tube (CCFT), or cold florescent light (CFL) tube - it either works or it doesn't. I'm inclined to think that your inverter is failing (it hasn't gone completely since it worked for a second...)

How many backlight tubes are in your LCD (count the number of wires that originate from the LCD to the inverter and divide by two)? If you have more than one tube, then the chances of both tubes failing (without actually being broken) is really nil nil. If you have only one tube, then the chances of your tube failing is still pretty darn close to being nil...

Of course, you can also meter the two contacts on the inverter - where the backlight plugs in - you oughta get somewhere around 1500V. Used to know someone who tested inverters by sticking his finger at the backlight connector - if you smell burnt flesh, there's nothing wrong with it.

bobchang
Light Poster
38 posts since May 2004
Reputation Points: 10
Solved Threads: 2
 

Thanks alot man that really helped me out! And I'll just use a volt meter I'm not that daring of a person :)

blicraft
Newbie Poster
2 posts since May 2004
Reputation Points: 10
Solved Threads: 0
 

This article has been dead for over three months

Post: Markdown Syntax: Formatting Help
You