GMC Sierra Denali Owner's Manual page 387

Starter Switch Check Automatic Transmission Shift Lock
Contr-l System Check
When you are doing this check, the vehicle
could move suddenly. If it does, you or others
could be injured. Follow the steps below.
1
1.
2.
3.
Before you start, be sure you have enough room
around the vehicle.
Firmly apply both the parking brake and the regular
brake. See Parking Brake
on
page 2-22 if
necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
I
_/hen you are doing _.. check, tl vel le
could move suddenly. If it does, you or others
could be injured. Follow the steps below.
I
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. See Parking Brake
on
page 2-22 if necessary.
Be ready
to
apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the key to the RUN
position, but don't start the engine. Without applying
the regular brake, try to move the shift lever out
of PARK (P) with normal effort. If the shift lever
moves out of PARK (P), your vehicle needs service.
6-1
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