Fiat 500 ABARTH 2015 Owner's Manual page 21

2. Rotate the screw located on the side of the Key Fob
using a small screwdriver.
Key Fob Screw Location
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 19
3. Take out the battery case. Remove and replace the
battery observing its polarity.
Battery Case Removed
4. Refit the battery case inside the Key Fob and turn the
screw to lock it into place.
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