1. Remove the VAD check valve (one-way). (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION)
2. Blow through A and verify that air flows from B.
3. Blow through B and verify that air does not flow from A.

Variable air duct (vad) control solenoid valve inspection (l3)
Idle air control (iac) valve inspectionMazda 6 Service Manual: Adjusting the Vents
Directing airflow
To adjust the direction of airflow, move the adjustment knob.
NOTE
When using the air conditioner under humid ambient temperature conditions,
the system may blow fog from the vents. This is not a sign of trouble but a
result of humid air being suddenly cooled.
The air ...
Mazda 6 Service Manual: Battery inspection
Battery
Inspect the battery in the following procedure.
Test load chart
Battery positive voltage with load
Back-up Current
1. Verify that the engine switch is at OFF and that the key has been removed.
2. Disconnect the negative battery cable.
3. Measure the back-up current between the n ...