Chevrolet Optra 2004 Owner's Manual page 72

At times you may notice a decrease in range. This is
normal for any remote keyless entry system. If the
transmitter does not work or if you have to stand closer
to your vehicle for the transmitter to work, try this:
•
Check the distance. You may be too far from your
vehicle. You may need to stand closer during
rainy or snowy weather.
•
Check the location. Other vehicles or objects may
be blocking the signal. Take a few steps to the
left or right, hold the transmitter higher, and
try again.
•
Check to determine if battery replacement is
necessary. See "Battery Replacement" under
Remote Keyless Entry System Operation on
page 2-4.
•
If you are still having trouble, see your dealer or a
qualified technician for service.
2-4
Remote Keyless Entry System
Operation
The following functions are available if your vehicle has
the remote keyless entry system:
W
(Unlock): Press this button to unlock all of the
doors. If all of the doors and the trunk or liftgate
are closed, the hazard lamps will flash twice to indicate
that unlocking has occurred. The theft-deterrent
system will deactivate and the security indicator will
turn off. The security indicator is located on the base
of the driver's door lock.
If a door is not opened or if the engine is not started within
30 seconds after pressing unlock on the remote keyless
entry transmitter, all of the doors will automatically relock
and the theft-deterrent system will reactivate.