1. Remove the charcoal canister.
2. Plug the atmosphere side port and purge solenoid valve side port of the charcoal canister.
3. Blow air into the charcoal canister from the fuel tank side port and verify that there is no air leakage.

Emission system
Evaporative gas check valve (one-way) inspection (l.h.d.)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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Mazda 6 Service Manual: Instrument cluster repair
Note
The needle of speedometer or tachometer may continue to rotate
clockwise until it indicates over maximum graduation. If a customer
complains of this concern, repair the needle position according to the
following steps.
1. Verify the concern.
2. Turn the ignition switch to LOC ...