Leakage check - AR42.50-P-0001-09MB

The ignition must be switched off.

1. Release pressure from booster circuit (depress brake pedal approximately 30 times).
2. Switch on the ignition and wait until the motor-and-pump assembly is deactivated.
3. Switch off the ignition and record the pressure.

   Do not operate brake pedal.

4. Wait 30 minutes then switch the ignition back on.

   Pressure loss < 20 bar and motor-and-pump assembly does not restart: System OK.

   Pressure loss >20 bar and motor-and-pump assembly starts to run:

   Brake booster hydraulic unit is defective.