See also:

Never leave these keys in the vehicle.
Additional or replacement keys. If you still have a key, the key number is not necessary when you need extra NISSAN Vehicle Immobilizer System keys. Your dealer can duplicate your existing key. ...

NISSAN vehicle immobilizer system
The NISSAN Vehicle Immobilizer system will not allow the engine to start without the use of the registered key. If the engine fails to start using a registered key (for example, when interference ...

Anti-freeze
In the winter when it is anticipated that the temperature will drop below 32°F (0°C), check the anti-freeze to assure proper winter protection. For details, see Engine cooling system in the M ...