To complete the work you will need a ruler or tape measure.
Sequence of execution
1. Prepare the car for work ("Preparing the car for maintenance and repair").
2. Place a ruler or tape measure near the pedal and measure the distance from the floor to the outer surface of the brake pedal.
3. Pressing the pedal with your hand, lower it until you feel an increase in resistance to the pedal's movement.
(Data taken from the specified website: LadaMan.ru)
We repeat the measurements. Based on the difference between the obtained values, we determine the free play.
Warning! Having free travel in the brake pedal ensures that after braking is stopped, the pistons of the master cylinder return to their original position, and as a result, there is no excess pressure left in the brake hydraulic drive. When the brake light switch is set so that it limits the rearward travel of the brake pedal, the brake system will be able to maintain pressure that will cause the brake pads to continuously apply the brakes.
Recommendation. If the free travel of the brake pedal is less than the optimum value, it is necessary to adjust the position of the brake light switch ("Brake Light Switch - Checking and Replacing"). Increased free travel of the brake pedal may be caused by play in the drive mechanism. Worn parts need to be replaced. The cause of the malfunction may also be the presence of air in the brake hydraulic drive or a malfunction of the master brake cylinder. The detected malfunction must be corrected ("Service brake system drive").