If your car remote has a dead battery or is just malfunctioning, you can still turn off your alarm with the key. Cars that have an alarm system also have a security system that matches a chipped key code to the car when you turn the ignition or put it in the door. If you have an aftermarket alarm, you may have to call the manufacturer for help, as the alarm system is not usually set to work with your car key.
Put your key into the driver’s-side door lock. If you have a push-button key, you’ll have to find the hidden key inside of it, which is used to get into your car if the remote isn’t working. Look for a small button on the side of the key fob that you can press in with your fingernail or slide over to release a small key.