Ford 1997 Crown Victoria Manual page 123

Additional transmitters may be purchased from
your dealer (remote entry system will work with
up to four transmitters). Follow the same
programming procedure as above.
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.
NOTE: All transmitters to be used on your
vehicle must be
programmed/reprogrammed at the same
time.
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