Hummer 2007 H3 - Manual (Page 135)

Be sure that people and objects are clear of the
garage door or security device you are
programming. When programming a garage door,
it is advised to park outside of the garage.
If you do not know if your garage door opener is a
fixed code or rolling code device, open your
garage door opener’s remote control battery cover.
Your garage door opener is a fixed code device if
there is a panel of switches. If not, your garage
door opener is a rolling code device.
Programming Universal Home
Remote — Fixed Code
Fixed Code garage door openers are used for
garage doors produced prior to 1996. Fixed code
uses the same coded signal every time, which
is manually programmed by setting DIP switches
for a unique personal code.
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