Chevrolet 1999 Express Van Owner's Manual page 74

Side Sliding Door
Move the button up to engage the security feature.
Move the button down to return the door locks to
normal operation.
2-6
Move the button up to
engage the security
feature. Move the
button down to return
the door locks to
normal operation.
Keyless Entry System (If Equipped)
If your vehicle has this option, you can lock and unlock
your doors from about 3 feet (1 m) up to 30 feet (9 m)
away using the remote keyless entry transmitter supplied
with your vehicle.
Your keyless entry system operates on a radio frequency
subject to Federal Communications Commission (FCC)
Rules and with Industry Canada.
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