Chevrolet 2003 Silverado 1500 Pickup Owner's Manual page 97

Delayed Locking
If your vehicle is a Crew Cab, it may be equipped with
this feature. When you lock the doors using the
power lock switch or the remote keyless entry
transmitter with any door open three chimes will signal
that delayed locking is being used.
Five seconds after the last door is closed, all the doors
will lock. All doors can be re-opened for up to five
seconds from the time the last door is closed.
You can lock the door immediately using the power
door lock switch or the optional remote keyless
entry transmitter a second time.
This feature will not lock the doors if the key is in the
ignition.
To enable or disable the delayed locking feature, do the
following:
1. Press and hold the power door lock switch on the
driver's door in the lock position.
2. Press the remote keyless entry transmitter unlock
button twice.
Programmable Automatic Door
Locks
If your vehicle has power door locks, it is equipped with
a feature that enables you to program the door locks.
Your vehicle left the factory programmed to
automatically lock all doors when the vehicle is out of
PARK (P), and all doors unlock when the vehicle is
in PARK (P). You can set the automatic door lock
feature to unlock the doors you select once the vehicle
is in PARK (P).
If your vehicle has a manual transmission it left the
factory programmed to lock all doors when the vehicle
speed is greater than 8 mph (1 2 km/h) for two seconds,
and unlock all doors once the key is removed from
the ignition. You can set the automatic door lock feature
to unlock the doors you select once the key is removed
from the ignition.
The following instructions detail how to program your
door locks.
If the feature is disabled, the doors will lock immediately
when a power door lock switch or remote keyless
entry transmitter button is pressed.
2-1 0