How to Replace the Key Fob Battery in a Volvo S80

1. Slide the spring loaded catch to the side.
2. Pull the key blade straight out of the remote key.
3. Insert a small screwdriver in the hole behind the catch and carefully pry up the cover, keeping the buttons facing upward.
4. Pry out the old battery with a screwdriver, noting its (+) and (–) sides.
5. Insert the new CR 2430, 3V battery with the (+) side downward.
6. Press the cover into place, then slide the key blade into its groove and press until it clicks.

• Replace the battery when Low battery in remote control is shown or the locks do not react after several attempts.
• Avoid touching the battery's contact surfaces.
• The remote key takes one CR 2430, 3V battery only.

Source: 2016 Volvo S80 owner's manual, PDF pages 149, 150. 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.