1. Connect WDS or equivalent to the vehicle DLC-2 16-pin connector located as shown in the figure.

2. Perform KOEO/KOER self-test.
After repair procedureMazda 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: Troubleshooting procedure
Basic flow of troubleshooting
DTC troubleshooting flow (on-board diagnostic)
Diagnostic trouble codes (DTCs) are important hints for repairing
malfunctions that are difficult to simulate.
Perform the specific DTC diagnostic inspection to quickly and accurately
diagnose the malfunction.
The ...