Potential problem diagnosis for CB3-431 very dim screen

OK220

Hey folks, 

I am asking a question in order to possibly gain a bit more insight into the possible problem with my CB3-431 Chromebook. Whilst using it I hit the area to the right of trackpad: fairly hard (was heat of the moment kinda stuff hah) and the screen suddenly went very dim, almost black, but possible to see if you looked in closely/held a torch up to it. 

I've tried taking to repair shops several times but have been unsuccessful due to lockdown closures/impending lockdown affecting spare parts delivery. Been looking into possibly buying the necessary parts and repairing it myself. I would have pretty confidently assumed that it might be a problem with the backlight or inverter but since these parts do not seem to be in the general region I hit I'm wondering if there's a possible other explanation for this problem? 

I have connected it to an external monitor via a HDMI and the screen brightness is fine for the external monitor.

Thanks in advance for your answers.

billsey

It sounds as if the LED back light isn't lighting any longer. The circuitry for that is integrated into the screen itself so if it's truly broken it'll mean a screen replacement. It's possible, however, that the cable that goes between the screen and motherboard has just been jostled enough to cause the symptoms. The only real way to test is to open it up and reseat the cable at both ends and that's pretty deep into disassembly...

billsey

It sounds as if the LED back light isn't lighting any longer. The circuitry for that is integrated into the screen itself so if it's truly broken it'll mean a screen replacement. It's possible, however, that the cable that goes between the screen and motherboard has just been jostled enough to cause the symptoms. The only real way to test is to open it up and reseat the cable at both ends and that's pretty deep into disassembly...