Chevrolet 2003 Silverado 1500 Pickup Owner's Manual page 513

Automatic Transmission Shift Lock
Control System Check
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
.
the
e
When you are doing this check, the vehicle
could move suddenly. If it does, you or others
could be injured. Follow the steps below.
On
I
I
1.
2.
3.
Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
Firmly apply the parking brake. See Parking Brake
on
page 2-44 if necessary.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
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.
e
ignition key to LOCK in each shift lever position.
With an automatic transmission, the key should turn
to LOCK only when the shift lever is in PARK (P).
With a manual transmission, the key should turn to
LOCK only when you press the key release button.
all vehicles, the key should come out only in LOCK.
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