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 System [Manual Air Conditioner]
Outline
Refrigerant pressure sensor adopted in which refrigerant pressure is changed
into a linear electric signal and precise information is transmitted.
Climate control unit with enlarged operation dials and switches adopted
Structural View
System Wiring Diagram
...
Passenger Sensing System [Two Step Deployment Control System]
Purpose
The passenger sensing system detects whether or not there is an occupant
on the passenger seat to control the operation (deployment) of the passenger-side
air bag system corresponding to the detected condition.
Function
Measures the total seated weight on the passen ...
Low Engine Coolant Temperature Indicator Light (Blue)/High Engine Coolant Temperature
Warning Light (Red)
Purpose
Low engine coolant temperature indicator light (blue)
The low engine coolant temperature indicator light (blue) notifies the driver
that the engine coolant temperature is low and vaporization of the fuel is difficult.
High engine coolant temperature warning light (red)
...