The side mirrors on this Kia Rio are slack. Time to fix this rattling issue.
Step 1: The Access Panel.
The mounting hardware is hidden behind a plastic panel. Using a knife I carefully pried the panel off.
Step 2: Tightening.
Using an elbow type Phillips head screwdriver, I tightened the 3 screws holding the mirror in place. I did the same process for example other mirror.
Now the mirrors are secure and safe for the road.