The installation manual gives all the answers.
Two dots means there is power to the controller with no trailer connected.
If the manual lever is activated it will display N.C. Then after 15 seconds it will display
". ." . Then after 15minutes the controller will go to power save with a blank screen.
Boost indication shows only when a trailer is connected. ".C" means trailer connected no boost. ".C." Means trailer connected with boost.
On my IPAD the link I gave for the installation manual does not work. Not sure with a computer but if it does not I am sorry. But the instruction manual can be down loaded from the Tekonsha web page.
