What to Do When Your Fiat 500 Key Fob Stops WorkingIf your Fiat 500 key fob stopped functioning, you have a few options. You might try replacing the battery, reprogramming the device or calling a locksmith for help.In most instances, a dead coin battery is the reason for the key fob not working. https://nebook.forthenext.org/index.php?mid=Youtube&document_srl=3373106