1. Start the on-board diagnostic test mode.
2. First press the POWER button, then simultaneously press AUDIO CONT button for 2 seconds or more.


Caution
3. To stop the on-board diagnostic test mode, turn the ignition switch to the LOCK position.
Supplier identification procedure
Dtc tableMazda 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: Vehicle speedometer sensor (vss) removal/installation
Caution
Water or foreign objects entering the connector can cause a poor
connection or corrosion. Be sure not to drop water or foreign objects on the
connector when disconnecting it.
If foreign materials are stuck to the VSS, disturbance by magnetic
flux can cause sensor output to be ...