On-Vehicle Inspection

INSPECT BRAKE BOOSTER
1. Air tightness check.
  1. Start the engine and stop it after 1 or 2 minutes. Slowly depress the brake pedal several times.
    HINT:
    
    If the pedal can be depressed to the floor the first time, but on the 2nd and 3rd time cannot be depressed as far, the booster is airtight.
  2. Depress the brake pedal while the engine is running, and stop the engine with the pedal depressed.
    HINT:
    
    If there is no change in the pedal reserve distance while holding the pedal for 30 seconds, the booster is airtight.
    
    Fig 1: Inspecting Brake Booster
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Operating check.
  1. Depress the brake pedal several times with the ignition switch off and check that there is no change in the pedal reserve distance when the pedal is depressed.
  2. Start the engine with the brake pedal depressed.
    HINT:
    
    If the pedal goes down slightly, operation is normal.
INSPECT VACUUM CHECK VALVE
1. Check the vacuum check valve.
  1. Slide the clip and disconnect the vacuum hose.
  2. Remove the vacuum check valve.
    
    Fig 2: Checking Vacuum Check Valve
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Check that there is ventilation from the booster to the engine, and no ventilation from the engine to the booster.
  4. If any fault is found, replace the vacuum check valve.
    
    Fig 3: Checking Ventilation From Booster To Engine, And No Ventilation From Engine To Booster
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002