Insufficient braking efficiency
| Cause of malfunction | Method of elimination |
| 1. Brake fluid leaking from the front or rear brake wheel cylinders. | 1. Replace defective wheel cylinder parts, wash and dry the pads and drums, bleed the brake drive. |
| 2. Air in the brake system. | 2. Remove air from the system. |
| 3. The rubber seals in the master brake cylinder are damaged. | 3. Replace the seals and bleed the system. |
| 4. The rubber hoses of the hydraulic drive system are damaged. | 4. Replace the hoses. |
Spontaneous braking with the engine running
| Cause of malfunction | Method of elimination |
| 1. Air leak in the vacuum booster between the valve body and the protective cap. | 1. Replace the vacuum booster. |
Incomplete release of braking of all wheels
| Cause of malfunction | Method of elimination |
| 1. There is no free travel of the brake pedal due to the incorrect position of the brake light switch. | 1. Adjust the position of the switch. |
| 2. The protrusion of the vacuum booster adjusting bolt relative to the mounting plane of the master cylinder exceeds 1.25-0,2 mm. | 2. Adjust the position of the adjusting bolt (fig. 6-2). |
| 3. The vacuum booster valve body is jammed. | 3. Replace the vacuum booster. |
| 4. The compensation hole in the master cylinder is clogged. | 4. Clean the hole and bleed the hydraulic drive system. |
| 5. Swelling of the rubber seals of the master cylinder due to gasoline, mineral oils, etc. getting into the liquid. | 5. Thoroughly flush the entire system with brake fluid, replace damaged rubber parts, bleed the hydraulic drive system. |
| 6. Seizure of the master cylinder piston. | 6. Check and, if necessary, replace the master cylinder, bleed the drive system. |
Braking of one of the wheels with the brake pedal released
The original can be seen on the website: VazBook.ru
| Cause of malfunction | Method of elimination |
| 1. The rear brake shoe tension spring has weakened or broken. | 1. Replace the spring. |
| 2. Seizure of the piston in the wheel cylinder due to corrosion. | 2. Disassemble the cylinder, clean and wash the parts, replace the damaged ones. |
| 3. Swelling of the wheel cylinder sealing rings due to ingress of fuels and lubricants into the liquid. | 3. Replace the rings, flush the hydraulic drive system with brake fluid. |
| 4. No gap between the pads and the drum. | 4. Adjust the parking brake. |
| 5. Violation of the provision | 5. Tighten the mounting bolts, |
| calipers relative to the brake disc when loosening the bolts securing the brake pad guide to the steering knuckle. | replace damaged parts if necessary. |
| 6. Increased brake disc runout (more than 0.15 mm). | 6. Grind the disc, if the thickness is less than 9 mm - replace the disc. |
Skidding or pulling the car to the side when braking
| Cause of malfunction | Method of elimination |
| 1. Brake fluid leak in one of the wheel cylinders. | 1. Replace the seals and bleed the system. |
| 2. Seizure of the piston of the wheel brake cylinder. | 2. Check and eliminate piston jamming in the cylinder; replace damaged parts if necessary. |
| 3. Blockage of any tube due to a dent or clog. | 3. Replace the tube or clean it and bleed the system. |
| 4. Different tire pressure. | 4. Adjust the pressure. |
| 5. Incorrect wheel alignment angles. | 5. Adjust the angles. |
| 6. Contamination or oiling of discs, drums and linings. | 6. Clean the brake parts. |
| 7. Incorrect installation of the pressure regulator. | 7. Adjust its position. |
| 8. The pressure regulator is faulty. | 8. Adjust it or replace it. |
Increased brake pedal force
| Cause of malfunction | Method of elimination |
| 1. The air filter is clogged. | 1. Replace the air filter. |
| 2. The vacuum booster valve body is jammed. | 2. Replace the vacuum booster. |
| 3. The hose connecting the vacuum booster and the engine intake pipe is damaged, or its fastening on the fittings has become loose. | 3. Replace the hose or tighten its clamps. |
| 4. Oxidation of the metal brake pedal bushings or drying out of the grease in the pedal bushings. | 4. Replace worn parts or grease. |
Squealing or screeching brakes
| Cause of malfunction | Method of elimination |
| 1. Weakening of the rear brake shoe tension spring. | 1. Check the tension spring, replace it with a new one if necessary. |
| 2. Ovality of the rear brake drums. | 2. Ream the drums. |
| 3. (Oiling of friction linings. | 3. Clean the pads with a wire brush, using warm water and detergents. Eliminate the cause of liquid or grease getting on the brake pads. |
| 4. Wear of linings or inclusion of foreign bodies in them. | 4. Replace the pads. |
| 5. Excessive runout of the brake disc or uneven wear. | 5. Grind the disc; if the thickness is less than 9 mm, replace the disc. |