Follow the the user guide for easy setting of your lighting features in the quick Link to Droid Turbo User Manual, http://cache.vzw.com/multimedia/mim/motorola-droid-turbo/smart-motorola-droid-turbo-ug.pdf
To add: Go into your user settings find Display tap to go in then Tap Sleep you have from 15 sec to 10 min, till your Display Times out again. you also have setting called Daydream, on my phone I have it set to off..
The timeout display has nothing to do with the screen blanking out on a call especially if the phone is held up to the face. Unless you change it, the power button can wake the screen to allow you to put in numbers from the dialer. Also don't cover the proximity sensor when you are using the phone as a speakerphone. If it isn't covered during speakerphone mode, then the normal screen timeout would be in effect.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.