What is the difference between two car keys?

[LeRylee]

Some cars have no difference, while others do. Some cars have a spare key that is just a mechanical key, while others have a spare key that is the same as the main key—a remote key. The specific details are as follows: 1. It is recommended that car owners usually keep the spare key at home, so that if the main key is lost, they can go home to get the spare key to unlock the car door and start the engine. If the spare key is a mechanical key, the car door can be unlocked directly using the lock hole on the door. 2. If the main key is lost, it is important to go to the 4S store immediately to have the technician disable the lost main key, and then get a new key. Remote keys have internal batteries, which will run out after prolonged use. If the battery is dead, the remote function will fail. Therefore, car owners should replace the battery in time when the remote key's power is low to avoid delays in using the car.