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 InspectionStart Stop Unit
Purpose
Performs control of several systems based on input/output signals from switches.
Function
The start stop unit controls systems based on the input/output signals.
The functions which are controlled are as follows:
Control Table
Control ...
Driving In Flooded Area
WARNING
Dry off brakes that have become wet by driving slowly, releasing the accelerator
pedal and lightly applying the brakes several times until the brake performance
returns to normal:
Driving with wet brakes is dangerous. Increased stopping distance or the vehicle
pulling to one side whe ...
Differential Oil Temperature Sensor Removal/Installation
WARNING:
Hot differential oil may cause severe burns. Do not perform maintenance while
differential oil is hot.
1. Disconnect the negative battery cable.
2. Disconnect the differential oil temperature sensor connector.
3. Remove the differential oil temperature sensor.
4. ...