GMC 2003 Savana Van Owner's Manual page 89

Battery Replacement
Under normal use, the battery in your remote keyless
entry transmitter should last about four years.
You can tell the battery is weak if the transmitter won't
work at the normal range in any location. If you have
to get close to your vehicle before the transmitter works,
it's probably time to change the battery.
Notice: When replacing the battery, use care not to
touch any of the circuitry. Static from your body
transferred to these surfaces may damage the
transmitter.
To replace the battery in the keyless entry transmitter,
do the following:
1.
Use an object like a coin to pry open the transmitter.
2.
Once the transmitter is separated, use an object
like a pencil to remove the old battery. Do not use
a metal object.
side down.
no moisture can enter.
keyless entry transmitter for seven seconds to
resynchronize the transmitter.
3. Remove and replace the battery, positive (+)
4. Snap the transmitter back together tightly to be sure
5. Press and hold LOCK and UNLOCK on the remote
6. Check the operation of the transmitter.
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