GMC Sierra Denali Classic 2007 Owner's Manual page 458

Automatic Transmission Shift Lock
Control System Check
CAUTION:
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When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
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 109.
Be ready to apply the regular brake
immediately if the vehicle begins to move.
3. With the engine off, turn the ignition to RUN,
but do not 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), contact
your GM Goodwrench
458
®
dealer for service.
Ignition Transmission Lock Check
While parked, and with the parking brake set,
try to turn the ignition to LOCK in each shift lever
position.
•
The ignition should turn to LOCK only
when the shift lever is in PARK (P).
•
The ignition key should come out only
in LOCK.
Contact your GM Goodwrench
is required.
®
dealer if service