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: Pcv valve inspection
1. Disconnect the negative battery cable.
2. Remove the intake maniforld.(see INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)
3. Remove the PCV valve.
4. Blow through the valve and verify that air flows as specified.
If not as specified, replace the PCV valve.
Specification
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Mazda 6 Owners Manual: Drive shaft removal/installation
Caution
Performing the following procedures without first removing the ABS
wheel-speed sensor may possibly cause an open circuit in the harness if it
is pulled by mistake. Before performing the following procedures, remove the
ABS wheel-speed sensor (axle side) and fix it to an appropri ...