1. Performance check.
A) After depressing the brake pedal a few times with the engine off, check that there is no change in the pedal back-up travel.
b) Depress the brake pedal and start the engine. If the pedal goes down a little, then the operation is normal.
2. Leak test.
A) Start the engine and stop the engine after one or two minutes. Slowly depress the brake pedal several times. If the pedal goes the farthest down the first time, then the booster is sealed.
b) Depress the brake pedal while the engine is running, then stop the engine without releasing the pedal. If within thirty seconds there is no change in the amount of power reserve of the pedal while keeping it pressed, then the amplifier is sealed.