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Thank you Camille for the update, keep me posted. I'm on-call tomorrow (er today) so may not respond to ? or results immediately.
With the laptop on, if you point a bright flash light at the screen can you see a picture where the beam strikes the screen? (or hold the laptop in the sunlight)
If so, then it seems the inverter is not working/connected properly or may have malfunctioned if you do have all the cables connected back correctly.
The answer that you suggest, ie shinning a light at the screen does work and the screen is displaying a picture.
The problem is its an LED backlight not CCFL and I cannot find any information or data related to an "inverter" for an LED. Do LED Backlight require "inverters", if so why/how is there no information listed for possible replacement.
For CCFL (which I've replaced before) there are both additional connections and a list of separate parts.
I need more help, sorry.
Sorry, I missed the part that it's a LED. Yes you're correct that this doesn't require an inverter.
Things that come to mind is all the cables are correct & undamaged, then the problem could be to do with the latch switch in the lid, a setting on the laptop which turns off the backlight or damage to the motherboard itself or faulty screen.
Is this an exact replacement please?
It is an exact replacement LCD - LTN140AT08. No apparent cable damage, it only has one tiny 2-3 cm connector at bottom of LCD.
Laptop has a separate on/off switch for screen and by doing your light trick, have verified it is on. I do not see any other connectors either in the hinges or ??? It does seem to have small wire extending from the connector all the way around the screen and returning to the hinge area but no connections are visible. I've also noted that the covering bezel has a small (~1cm) metal plate (w/blue vertical line) ~ 1/4 distance from the right upper corner. I have thought this might be a magnetic and/or ground, but even w/the bezel snapped back into place, I have no "backlight".
That wire is probably the wireless antenna.
If you put the old screen back in does the backlight come on?
If so then it seems the new screen is defective as that will also prove the ribbon cable is ok.
Sorry, I mentioned that much earlier in the original post. Original screen was re-installed and it too has no backlight. It did work albeit minus ~ 2 inches from the left side, but now nada same as new screen.
That would point to another part failure, but I've had no luck in finding anything else. I thought your idea about a hinge switch was possible, but it should light up on re-boot and I get absolutely nothing.
PS - I noted that I would be at hospital all day, sorry for the delayed response.
Dan you are correct, prior to the exchange, the old LCD worked (backlight and all) minus ~ 2 inches on the left side (reason for replacement). Sony Laptop VPC CW13FX.
PS - Off to hospital now, sorry if I don't get back to you until this evening.
Hi Dan, Paul, Camile, Hongkongpom et. al
I've tried the old screen again just to verify that it does not work - Verified. Just for "grins" I've pulled the entire laptop apart (whew - 40 screw later) and do not see any specific "loose" connections on the main board. I can turn on the lapto (minus HD) but again no light on the old board - decided to try that first since its already defective and in case I do something funky.
If anyone has a schematic/diagram of this particular Sony MB or layout and can find the connection to the video (nVidia Geforce ? model), perhaps I can test the output to the screen, otherwise I think this is a lost cause.
Thanks for the effort/feedback, I hope someone has further thoughts.
Thank you for that suggestion. I've checked the hinges - removed the screws, then replaced them w/o any luck. After removing, I tried to look behind to see if there was any kind of switch, but I've not been able to find anything that even remotely looks like a reed/button switch. If anyone knows if and more importantly where it might exist, that might actually be the problem since I can't see anything that has been disconnected, burned or otherwise shorted on the board or connector.
Thanks again for the idea.