1993 Buick Century Owner's Manual - Page 70

For battery replacement use two DuracelP batteries, type DL-2016, or a similar type. To replace batteries: 1. Remove the screw from the back cover. 2. Lift off the front cover, bottom fEstst, half 3. Remove and replace the batteries.. Put them in following the diagram under the batteries on the inside of the cover. 4. Replace the front cover.Make sure the cover is on tightly, so water won't get in. Replace the screw in the back cover. 5. Check the transmitter operation. 68