LCD4041 backlight not working

ghost2501 · Post by **ghost2501** » Mon Jan 23, 2006 12:32 pm

I got two more of theese displays and one has a backlight that dosent work. The display works fine as far as I can tell It just seems there is no backlight at all. It is a rev 1.02 and is the only one with a silver metal face instead of grey metal.

I was wondering if this is common and if I can do anything about it on my end and if not about how economical is it to send back displays for work? I have one other display that lights up just wont communicate.

I have a laser engraving/cutting machine and I can make a custom clear side pannel for my pc and I plan on putting 2 or 3 of theese into my pc. I can also laser cut custom mirror faceplates etc. and I can laser etch the mirror off the back shaped like an email icon etc. and put led lights behind the email icon. just to let you know what I plan on doing with theese. You might even want to trade some custom inlaid mirror license plates or 3-D inlaid mirror case badges with matrix orbital logo for fixing the displays. anyway thank you

Tom · Post by **Tom** » Fri Jan 27, 2006 2:03 pm

Hi ghost2501,

I apologize for not replying sooner. I have been out of the office for a couple days.

It may not be economical to send these displays back for repair. It will depend on the damage of the displays. Also, these displays are quite old, so I might not be able to get a certain part for repair. Do you have a multimeter? I can help you with inspecting your units, and you can replace the parts on your end. If you would like me to look at the units, then email me at tlam@matrixorbital.ca

Best Regards,

ghost2501 · Post by **ghost2501** » Sun Feb 12, 2006 8:12 am

hello

I do have a multimeter one of my displays works fine in lcdc just no backlight and one dosent seem to connect. I can send you pictures of each if necessary. I was thinking maybe the resistor for the backlight wasnt working etc but If you can talk me through something for one or the other displays that would be great.

Tom · Post by **Tom** » Mon Feb 13, 2006 2:50 pm

For the unit without a backlight, the N-Channel mosfet used to drive the backlight might have gone bad. You may want to check the output to see if you get 5V turning on and off. Another thing that might happen with the display is the backlight LEDs may have burned out. If that is the case, then the display will need to be changed. The resistors may also have been blown too. There should be two 10ohm resistors in parallel with eachother on the input of the mosfet. If you get 5ohms for your reading, then your resistors are fine.

For the unit that doesn't connect, you can check whether there is -8V coming from pin 6 of the RS-232 chip. The RS-232 chip might be bad on the particular unit. I would be able to help you easier if you had an oscilloscope, so you can see any bits moving.

I hope this helps any of your trouble shooting. Let me know what you find out.

Best Regards,

ghost2501 · Post by **ghost2501** » Tue May 02, 2006 12:27 am

Hello for some reason the light is working now although dim. Anyway I was wondering waht the costs would be approx having one of theese fixed. the one that just has a blinking curson but seems 100% ok you said it may be a communications baud rate issue etc. also I noticed some have dimmer lights and some are quite bright and beautiful in comparison. Is there a replacement fix for a new brighter light? please save my day you guys are awesome

thanks

Raquel · Post by **Raquel** » Tue May 02, 2006 11:37 am

Hi ghost2501,

Our tech support person who knows the answer for your repair question is out of the country right now. I will forward your question to his email though, so that he may be able to see it when he gets the chance to check his email.

Thank you for your patience.