GMC 2001 Denali Owner's Manual page 98

To replace the battery in the keyless entry transmitter, do
the following:
1. Insert a dime in the slot between the covers of the
transmitter housing near the key ring hole. Remove
the bottom by twisting the dime.
2. Remove and replace the battery with a three
CR2032 or equivalent battery, positive (+) side up.
3. Align the covers and snap them together.
4. Resynchronize the transmitter.
5. Check the operation of the transmitter.
Resynchronization
Resynchronization may be necessary due to the security
method used by this system. The transmitter does not
send the same signal twice to the receiver. The receiver
will not respond to a signal that has been sent
previously. This prevents anyone from recording and
playing back the signal from the transmitter.
To resynchronize your transmitter, stand close to your
vehicle and press and hold the LOCK and UNLOCK
buttons on the transmitter at the same time for seven
seconds. The door locks should cycle to confirm
resynchronization. If the locks do not cycle, see your
dealer for service.
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volt
2-11