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My keyboard lights are not coming on. I just got this Mac as used. They just told me that the track pad does not work as far clicking. But it does sense your finger going over it. Will this cause the keyboard lights to not work?
You’ll need to pop the bottom cover off and do some inspection and testing. I’m thinking your system is liquid damaged ;-{ The keyboard is lit by a set of LED’s held in a plate that sits under the keyboard. So it can often get damaged by liquid seeping under the keyboard. This can also explain why the trackpad is also having problems. Review this guide: MacBook Pro 13" Unibody Mid 2012 Logic Board Replacement Jump down to Step 12 for the backlight connection. You’ll need to carefully test the voltage to see if its present (disconnected) If it is that’s a sign you’ll need to replace the backlight and you might as well replace the keyboard and trackpad as well if you see any signs of corrosion. 13” MacBook Pro Backlight plate for Sunrex keyboard (09-12)13” MacBook Pro Backlight plate for Darfon keyboard (09-12)13” Macbook Pro Trackpad and flex cable (11/12)
