Check Valve Operation Check

WARNING: This page is about a different variant/trim than selected.

Remove the check valve (Refer to MASTER CYLINDER ASSEMBLY AND BRAKE BOOSTER ASSEMBLY ).
CAUTION: Replace the check valve when it is faulty.

Using a vacuum pump, check operation of the check valve.

Vacuum pump connection	Normal condition
When connected to the booster side (1)	Vacuum is generated and maintained.
When connected to the engine side (2)	No vacuum is generated.

Fig 1: Testing Check Valve Using Vacuum Pump

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.