GMC Yukon Denali 2015 Owner's Manual page 371

10-80 Vehicle Care
3. Apply the parking brake and
start the engine.
For vehicles with electric parking
brakes, the parking brake cannot
be applied and the tires must be
chocked.
4. Shift the transfer case to
N (Neutral). See Shifting into
N (Neutral) under Four-Wheel
Drive on page 9-33 for the
proper procedure. Check that
the vehicle is in N (Neutral) by
shifting the transmission to
R (Reverse) and then to
D (Drive). There should be no
movement of the vehicle while
shifting.
5. With the transmission in
D (Drive), turn the engine off.
Caution
Failure to disconnect the negative
battery cable or to have it contact
the terminals can cause damage
to the vehicle.
6. Disconnect the negative battery
cable at the battery and secure
the nut and bolt. Cover the
negative battery post with a
non-conductive material to
prevent any contact with the
negative battery terminal.
7. Shift the transmission to
P (Park).
Caution
If the steering column is locked,
vehicle damage may occur.
9. Move the steering wheel to
make sure the steering column
is unlocked.
10. Release the parking brake.
11. Keep the RKA fob outside of
the vehicle, and manually lock
doors. Access vehicle same as
dead vehicle/fob process (back
up key in door lock).
Disconnecting the Towed Vehicle
Before disconnecting the towed
vehicle:
1. Park on a level surface.
2. Set the parking brake, shift the
transmission to P (Park).
3. Connect the battery.
4. Apply the brake pedal.
5. Start the engine, then shift the
transfer case out of N (Neutral)
to Two-Wheel Drive High. See
Four-Wheel Drive on page 9-33
for directions on shifting out of
N (Neutral).
6. Check that the vehicle is in
Two-Wheel Drive High by
shifting the transmission to
R (Reverse) and then to
D (Drive). There should be
movement of the vehicle
while shifting.
7. Shift the transmission to
P (Park) and turn off the ignition.