Hyundai Palisade key fob battery

Smart key (push-button start)

1. Start by freeing the hidden metal key: there is a latch or slide on the case, and the blade comes out once it moves.
2. Use the slot where the metal key sat. Twist, do not lever hard, and work along the seam until the halves separate.
3. Note which side of the old coin cell faces up (usually the side with the writing), lift it out with a plastic tool, and press the new one in the same way.
4. Reassemble, refit the emergency key, and check that the car sees the fob when you press start.

Hyundai smart keys usually have a button that releases the mechanical key; a flat tool in the gap then opens the case.

A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

A CR2450 is 24.5 mm across and 5.0 mm thick, much fatter than a CR2032. A thinner cell will rattle and lose contact, so buy the exact size.