1. Remove the vacuum hose..
2. Verify that air can be blown from the power brake unit side of the vacuum hose towards the vacuum pump side, and that air cannot be blown in the opposite direction.

If there is any malfunction of the inner check valve, replace it together with the vacuum hose as a single unit.
Vacuum Hose Removal/Installation
Vacuum Pump InspectionControl Valve Body [Fw6 A EL, Fw6 Ax EL]
Purpose/Function
The control valve body controls the hydraulic pressure generated by the oil
pump by each solenoid valve. In addition, the oil passages which introduce hydraulic
pressure to the pistons for each clutch and brake is formed by the switching
of each built-in shift valve. ...
Differential [Fw6 A EL, Fw6 Ax EL]
Purpose/Function
The differential absorbs the difference in the rotation speed between the
left and right driving wheels so that the vehicle drives smoothly when differences
occur due to cornering or driving on rough roads.
Construction
The differential consists of the ring ...
Rear Door Trim Disassembly/Assembly
1. Disassemble in the order shown in the figure.
1
Switch panel cover
2
Power window subswitch.
3
Fastener
4
Rear door trim
2. Assemble in the reverse order of disassembly.
...