Locate the small seam or notch on the key fob
Find the release button or latch for the mechanical key
Press the release button and remove the emergency key
Use the key blade or a small flat tool at the seam
Gently twist to separate the two halves of the fob
Work around the edge until the cover pops open
Remove or replace the battery if needed
Align the two halves and press them back together until they snap shut
Reinsert the mechanical key into place