Ford F-250/F-350 Super Duty key fob battery

Flip key

1. Swing the key blade open first. On most flip keys the cell lives in the body behind the hinge.
2. Find the seam or small slot on the body (often at the end away from the blade) and twist a coin or small flat screwdriver in it until the cover lifts.
3. Swap the coin cell, keeping the same face up as the one you removed, and do not bend the metal contact tab.
4. Close it up, check the blade still flips cleanly, and test the buttons at the car.

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.

Smart key (push-button start)

1. Find the small release on the edge or back of the fob and hold it while you pull out the metal emergency key.
2. Use the slot where the metal key sat. Twist, do not lever hard, and work along the seam until the halves separate.
3. Before you take the old cell out, look at its face. Put the new cell in with the same side showing, and avoid touching both faces at once.
4. Reassemble, refit the emergency key, and check that the car sees the fob when you press start.

Ford intelligent access fobs usually have a release for the emergency key. The key blade itself fits the pry slot.

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.