Dtc u2021Mazda 6 Service 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 Service Manual: Windshield Defrosting and Defogging
Press the windshield defroster switch. In this position, the outside air position
is automatically selected, and the air conditioner automatically turns on. The air
conditioner will directly dehumidify the air to the front windshield and side windows.
Airflow amount will be increased.
WARNING
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