How to Replace the Key Fob Battery in a Buick Lucerne

1. Insert a thin flat tool, such as a flat head screwdriver, into the notch along the transmitter's parting line, stopping when you feel resistance.
2. Twist the tool until the transmitter separates.
3. Take out the old battery without using a metal object.
4. Put in the new CR2032 or equivalent battery with the positive side facing down.
5. Snap the transmitter back together.

• Replace the battery when REPLACE BATTERY IN REMOTE KEY appears in the DIC.
• Do not touch the transmitter's circuitry, because static from your body could damage it.

Source: 2011 Buick Lucerne owner's manual, PDF pages 110, 208. Steps are summarized in our own words (AI-assisted, checked against the cited pages 2026-10-18). Other model years can differ; your manual has the final word.