1. Remove the clamps and vacuum hose.
2. Apply both suction and pressure to the engine-side hose, and verify that air blows only toward that side.

Air bleeding
Brake pedal inspectionMazda 6 Service Manual: Oil pressure switch removal/installation
Warning
When the transaxle and ATF are hot, they can badly burn. Turn off
the engine and wait untill they are cool before replacing ATF.
1. Disconnect the negative battery cable.
2. Remove the under cover.
3. Disconnect the cord assembly connector.
4. Remove the oil pressure switch.
...
Mazda 6 Service Manual: When Trunk Lid Cannot be Opened
If the vehicle battery is dead or there is a malfunction in the electrical system
and the trunk lid cannot be opened, perform the following procedure as an emergency
measure to open it:
1. Open the cover.
2. Move the lever to the left to fold the seatback.
3. Move the lever to the left to o ...