Display went dark

lordimac

New member
Hi, 3 Years ago I ordered a drive bay kit with an CF-635 (DMK635-TMF-LI-KU) from a german supplier (LC-Designs).

https://www.crystalfontz.com/product/CFA635TMFKU

The display went very dark over the time, it's hard to see the text on display during daytimes. It was running nearly 24/7 since the installation but with lcdproc setting for turning the backlight off during inactivity. For testing purposes I enabled the backlight during inactivity in the last few days.

So, is it possible to repair this by myself? As far as I know the display is inverted so the backlight is white, is it? If so, and you are using LED backlights, it should be possible to change these. Any words on this?

Thank you!
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CF Support2

Administrator
My apologies for the delay in getting back to you on this.

It is possible to repair the backlight yourself. We have some spare backlight assemblies if you are interested. It will make the repair much easier than replacing the individual LEDs.

To do the repair, you will need to disassemble the LCD carefully:

1 - Set the CFA635 face down on a soft, clean, ESD safe surface
2 - With small pliers, bend each for the tabs on the bezel away from the PCB
3 - Carefully, remove the bezel assembly from the PCB
4 - The LCD glass and elastomers will likely stay on the PCB when you do this. Keep note of the orientation of the LCD glass -- there is a bump on one end.
5 - Carefully lift the LCD glass and elastomers from the PCB
6 - The backlight should now be nicely in view
7 - The backlight will now need to be removed - there are A and K tabs on each end of the backlight assembly - remove the solder then lift off the backlight assembly.
8 - The LEDs are on the inside of the small boards on each end of the backlight assembly. If I recall correctly, the are 0403 (maybe 0603) - I can get you compatible part numbers if you want to go this route.
9 - Or, drop in a new backlight!

Let me know which way you want to go.
 

lordimac

New member
Well, I could order an replacement from you, but I'm from Germany and I think the shipping will be more expensive then replacement LEDs ordered from germany.
Do you have any pictures of the backlight assembly so I can imagine the work? It's not the first time for me soldering/replacing SMD LED, but want to be on the safe side.

If I order them by myself it would be important for me to get an part recommendation (Operating voltage, Light intensity, etc.).

Thank you
 

lordimac

New member
If possible for you, please send me an offer for the part including shipping to germany. If you don't want to write this here, you can also send me an Message (E-Mail, Private Message).
 

CF Support2

Administrator
I could offer up the backlight for free if you were to pick up the shipping charges. We normally send out via FedEx - so we are looking at US$50.00 to US$75.00 or more for that. We could take it to the post office and send it that way, rates look to be in the same price range for priority, and around US$6.00 for regular post. It's not our normal way of shipping so it may be a few days for someone to head down that way.

Shoot an email to support@crystalfontz.com and we'll go over the details in a support ticket.
 

lordimac

New member
Anyway, if it's possible for you to send this with regular post, then I would choose this. I don't care if it takes 2 or 4 weeks. :) Will send you an E-Mail in the next few minutes.
 

CF Support2

Administrator
My apologies for the late reply -- I haven't seen and email come in for you yet :(

I'll PM you my email and we'll try that way.
 

lordimac

New member
Still no informations and I don't get any reply per mail or private message. Whats wrong?!

Please, just tell me which LEDs I need... Too much waiting, sorry!
 

CF Support

Administrator
This is shipping to you today. Sorry about the wait. We put a little bonus item in the package for you as a sort of 'sorry we took so long' gift.
 

lordimac

New member
After some correspondence with german customs they released the package and it arrived today. Have to say thank you very much. Everything is as expected and the bonus was very suprising!
 

CF Support

Administrator
You're very welcome.

I believe we've also contacted you in a roundabout fashion to let you know about the 'bonus' updates.

Thanks again for your patience.
 
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