Vacuum Hose Check Valve Inspection (Power Brake Unit)

WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Remove the clamps and vacuum hose (power brake unit side).
For engine side, insert a small flathead screwdriver in the direction of the arrow shown in the figure, push the ring down and remove the vacuum hose. (L3)
Remove the clamps and vacuum hose (engine side). (AJ)

Fig 1: Removing Vacuum Hose
Courtesy of MAZDA MOTORS CORP.
Apply both suction and pressure to the engine side hose, and verify that air blows only toward that side.
- If air flows in both directions or not at all, replace the vacuum hose.
  
  Fig 2: Applying Both Suction And Pressure To Engine Side Hose
  Courtesy of MAZDA MOTORS CORP.