The system operates only when the driver is in the vehicle or within operational range while the key is being carried.
Starting the Engine
NOTE
If the vehicle is started and the key is not in the vehicle, the vehicle will not restart after it is shut off and the ignition is switched to off.
With the advanced keyless function

Without the advanced keyless function

NOTE
The engine may not start if the key is placed in the following areas:
Transmitter
Key Suspend FunctionMazda 6 Owners Manual: Immobilizer System
The immobilizer system allows the engine to start only with a key the system
recognizes.
If someone attempts to start the engine with an unrecognized key, the engine
will not start, thereby helping to prevent vehicle theft.
If you have a problem with the immobilizer system or the key, consult ...
Mazda 6 Owners Manual: Keys
WARNING
Do not leave the key in your vehicle with children and keep them in a place
where your children will not find or play with them: Leaving children in a
vehicle with the key is dangerous. This could result in someone being badly injured
or even killed. Children may find these keys to be ...