2003 GMC Envoy Owner's Manual - Page 76

Battery Replacement To replace the battery in the remote keyless entry transmitter do the following: touch any of the circuitry. Static from your body transferred to these surfaces may damage the transmitter. - ., .. ,- 1. Insert a thin coin in the slot between the covers of the transmitter housing. Gently pry the transmitter apart. 2. Remove and replace the battery with a three-volt CR2032 or equivalent battery, positive (+) side down. 3. Align the covers and snap them together 4. Check the operation of the transmitter. 2-7