Chosen Solution
I cannot fix using the suggested method. My Macbook Pro got updated to 10.14.6 and when I turned it ON, the fan started with loud voice and I cannot see battery sign in taskbar, I tried the Show Battery checkbox in system settings that too didnt work. Also my keyboard backlit is not working. The charger connector led switched color when I try Power key + Shift + ctrl + alt then it turns on again with same fan noise and no battery icon in taskbar.
Did you goto apple > about this mac > system profile ? Is battery registered there under power section ? Try installing an earlier version of OS X on your machine ?
