Start car a and move ac to recirculate.
Turn off radio and turn headlights to off not automatic.
Put car in neutral and turn car off. Our 2010 Edge with the gear shift in neutral just turn the key as far back as it will go, which is the accessory position. Ours is a 13 and no key so in neutral, no do not put foot on the brake, push start button until tow shows in little display on dash.
If you do not he a charge wire from the coach to car, the car will draw when you put the brakes on and when tail lights or flashers come on.
With a charge wire from coach to car you tail lights and turn signals and brakes will be running off the battery.
We ran ours down a time or two in the 2010 with key start by not putting the key in accessory position. The accessory position keeps the front wheels from locking. Your radio and headlights will operate if you leave them on.
Someone reaffirm this as it has been a while since it has been a while since we drove the 210 with key start.
Your manual should tell all this too.