1. Turn the ignition switch to ON position.
2. Turn the rear window defroster switch on.
Caution
3. Connect the positive (+) lead of the voltmeter to the positive side of each filament and the negative (−) lead to ground.
4. Gradually, slide the positive (+) lead from the positive side to the negative side and measure the voltage. Verify that the voltage decreases accordingly.
Mazda 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: Cruise control switch inspection
1. Disconnect the negative battery cable.
2. Remove the driver-side air bag module. (See DRIVER-SIDE AIR BAG MODULE
REMOVAL/INSTALLATION.)
3. Disconnect the cruise control switch connector.
4. Inspect for resistance and continuity between the cruise control switch
terminals using an ohmmeter. ...