Chevrolet 2003 Malibu Owner's Manual page 76

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 remote keyless entry
transmitter:
1. Use a flat object like a coin to separate the bottom
half from the top half of the transmitter.
2. Remove the battery and replace it with the new
o n e
Make
sure the positive side of the battery
faces up. Use one three-volt, CR2032, or
equivalent, type battery.
cover is on tightly, so water won't get in.
3. Put the two halves back together. Make sure the
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