GMC 1997 Safari Owner's Manual page 127

Universal Transmitter (Option)
This transmitter allows you to consolidate the functions
of up to three individual hand-held transmitters. It
will operate garage doors and gates, or with the
accessory package, other devices controlled by
radio frequency such as horneloffice lighting systems
and security systems.
The transmitter will learn and transmit the frequencies
of most current transmitters and is powered by your
vehicle's battery and charging system.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference,
and (2) this device must accept any interference
received, including interference that may cause
undesired operation.
This device complies with RSS-210 of Industry and
Science Canada. Operation is subject to the following
two conditions: (1) this device may not cause
interference, and (2) this device must accept any
interference received, including interference that may
cause undesired operation of the device.
Changes or modifications to this system by other than an
authorized service facility could void authorization to
use this equipment.
Programming the Transmitter
Do not use the transmitter with any garage door opener
that does not have the "stop and reverse" feature. This
includes any garage door opener model manufactured
before April 1, 1982.
Be sure that people and objects are clear of the garage
door you are programming.
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