I recently replaced the LCD cable on my x240, and then the screen.
The new LCD cable worked, but my old LCD cracked during the reinstall process, losing the left half of the screen, so I ordered a replacement using the right FRU (or whatever the part acronym Lenovo uses). Now when I try to boot the system, the logo shows up, but it's barely visible on the othewise dark screen. Keyboards/leds etc all work.
It definitely boots with logo, but extremely dark, looks like a black screen. I.e., the logo isn't bright like usual. Also, I can't tell what happens afterwards, the screen goes blank, but I'm not sure it's going on to Windows or what happens. It's not rebooting on its own though. The system definitely stays on until I power it off (and I can see the screen power off too).
This is happening with both LCD screens. I also tried the old LCD cable - exactly the same.
Any suggestions?
Thanks
PS: Any suggestions how I can disable the internal battery? Before I would do this with the BIOS, but now I can't get to that screen :-/
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It is not very likely, but the magnetic switch that turns off the LCD backlight when you close the lid could be stuck in the closed position. Worth investigating if the above leads to nowhere.Last edited: Jul 5, 2020esmail likes this. -
Do you have more information on that magnetic switch? I didn't even know there was such a thing.
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It is possible that a short cause the backlight to go out. I suspect they have a fuse soldered on the PCB near the eDP or LVDS connection.esmail likes this. -
That may take some time, plus it's not quite clear to me that I could do anything about the fuse on the motherboard :-/Mr. Fox likes this. -
Once you find it you could try momentarily bridging it to see if the backlight comes on, but if there is a dead short somewhere else that could result in harm. But, it would also immediately blow the fuse. That is probably not the case though. If I were going to take a guess, possibly a severe ESD situation would be the most likely cause.esmail likes this. -
I was planning to upgrade to a new Lenovo (T490 possibly), but not right away .. sigh.
Thanks. -
esmail likes this.
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Not a super-expert in electronics, so doubtful I could to much for others, but I'll give it a try for myself on this. Thanks for the encouragement. I may ping you for some additional tips when the time comes (hope you won't mind).Mr. Fox likes this. -
I am near Phoenix. If not for the COVID-19 lock-down bullcrap, I would still be traveling to Joliet a week every month and I'd offer to help you after work one evening. But, sure... feel free to send me a PM if you have any questions and I will try to help.
x240 boots with logo, but extremely dark, looks like a black screen.
Discussion in 'Lenovo' started by esmail, Jul 5, 2020.