Chosen Solution
I originally reviewed this machine with a few keys not functioning, one of those keys being ‘R’ so booting into recover mode hasn’t been an option. I originally opened this machine to clean the keyboard ribbon connector, I did that, then stripped the rest of the system down to fix a dent without causing harm to any components. I put the system back together and now it only boots to a grey screen. My only option is booting into safe mode with the ‘shift’ key or holding the ‘option’ key then selecting my hard drive. Strangely enough my keyboard works while booting but once the OS is loaded its not functional whats so ever. Please help, I’m running OS-X El Captain (10.11.6)
When you boot holding the option key you should then be able to select the recovery drive.
If you can get into System Preferences, open the keyboard panel take note of the keyboard driver being used and then delete it. Then add it back in so it’s refreshed. See if that solves it. Update (08/29/2017) Here’s where the keyboard drivers are located:
You want to remove the the one on the left then add it back
