Chosen Solution
Hi all, Since a few days my left shift key is not working. It;s possible due some liquid spill. I found some spots on the battery and the back on the touchpad. At all time all the letters are all caps. I managed to fix it with some software, Karabiner. Without configuring some settings it’s disabling the caps. But the shift key still isn’t working. Side note: An external usb apple keyboard is working fine, even the left shift. Also I reinstalled MacOS completely. Today I replaced the internal keyboard and backlight with no results. What can I do next? What are the possible fixes? Touchpad? Kind regards
From there, I would try a test trackpad cable and trackpad. Check the keyboard connector on the trackpad to see if any pins are corroded or burnt. Also check both sides of the trackpad cable (sometimes this is burnt, although I have replaced a few which were bad but didn’t look bad). If it is none of the above, it will be a logic board issue. Try the above first though to eliminate this being the case.
