Two switches are mounted at the brake operational pedal adjacent to the fulcrum; the upper switch is the stop lamp switch while the lower one is the ASCD switch. The brake pedal free height can be adjusted removing the locknut from the booster input rod and turning the input rod till the free height matches the standard measurements and make sure the tip of the input rod is inside the booster. After finishing the tightening of the locking nut on the booster input rod, there should be a specific clearance between the two lever switches at the place where the tips of both the screws of the switches contact the brake pedal, and this clearance can be adjusted by loosening the locking nut in the switch and turning the adjusting nut, in case the clearance does not conform to the required standards. Also check/do the following: confirm that the free pedal travel is within standard/factory set values and check tat the stop lamp is out when the pedal is released. With the engine running, measure the brake pedal depressed height, i.e., check the distance from the face of the pedal to the floorboards and compare the result with the specified dimension; if the distance is less than the specified dimension, look for the signs of leakage, air accumulation or damages of hydraulic system components.