How to Replace the Key Fob Battery in a Tesla Model S

1. Place the key fob button side down on a soft surface and release the bottom cover with a small flat-bladed tool.
2. Lift the old battery away from the retaining clips.
3. Insert the new CR2330 battery with the '+' side facing up, avoiding its flat surfaces.
4. Hold the bottom cover at an angle, align its tabs with the slots on the key fob, and press firmly until it snaps into place.
5. Test the key fob by unlocking and locking Model S.

• A message displays on the touchscreen when the battery is low; the battery lasts up to one year under normal use.
• Wipe the battery clean before fitting, since finger marks on the flat surfaces can reduce battery life.
• Keep new and used coin cell batteries away from children; swallowing can cause severe internal burns.

Source: 2026 Tesla Model S owner's manual, PDF pages 29, 30. 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.