Cause of malfunction | Remedy |
Increased brake pedal travel | |
Brake fluid leak from wheel cylinders Air in the brake system Damaged rubber seals in the master cylinder Damaged rubber brake hoses hydraulic brakes Increased brake disc runout (more than 0.15 mm) Leakage of brake fluid through the sealing cuffs of the pusher of the brake pressure regulator | Replace worn parts of wheel cylinders, wash and dry brake pads, brake discs and brake drums, bleed the brakes on the car Bleed air from brake system (bleed the brakes on the car) Replace seals and bleed brakes Replace brake lines and bleed brakes Grind the brake disc; if the thickness of the brake disc is less than 17.8 mm, replace it Replace the sealing cuffs of the brake pressure regulator |
Insufficient braking performance | |
Lubrication of linings of brake pads of brake mechanisms Jamming of pistons in wheel brake cylinders Complete wear of brake pads Overheating of the brakes Using brake pads with incorrect brake linings Incorrect adjustment of the brake pressure regulator Loss of tightness of one of the circuits of the brake system (accompanied by a partial failure of the brake pedal) | Wash and dry brake pads Eliminate the causes of jamming of the pistons in the wheel brake cylinders, replace the damaged parts, pump the brakes Replace brake pads Stop immediately and let the brakes cool down Use brake pads recommended by the manufacturer only Adjust brake pressure regulator actuator Replace damaged parts, bleed the brake system |
Incomplete release of all wheels | |
No free play on the brake pedal The protrusion of the adjusting bolt of the vacuum booster rod relative to the mounting plane of the brake master cylinder is broken Swelling of the rubber sealing cuffs of the main brake cylinder due to the ingress of gasoline, mineral oils, etc. into the brake fluid. Jamming of the piston of the main brake cylinder | Adjust brake pedal free travel Adjust the protrusion of 1.25-0.2 mm of the adjusting bolt of the brake booster rod Thoroughly flush the entire system with brake fluid, replace the cuffs, bleed the brakes Check and, if necessary, replace the main brake cylinder, bleed the brake system |
Braking of one wheel with the brake pedal released | |
Broken or weakened rear brake pad return spring Seizure of the piston in the wheel brake cylinder due to contamination or corrosion of the cylinder body Swelling of the sealing cups of the wheel brake cylinder due to the ingress of gasoline, mineral oils, etc. into the brake fluid. Violation of the position of the brake caliper relative to the brake disc when the bolts securing the brake pad guide to the steering knuckle are loosened Incorrect adjustment of the parking brake system | Replace rear brake pad spring Dismantle the brake cylinder, clean and wash the parts, replace the damaged parts, bleed the brake system Replace the cuffs, flush the hydraulic brake system with brake fluid, bleed the brakes on the car Tighten the brake caliper mounting bolts, replace damaged parts if necessary Adjust the parking brake system |
Skidding or pulling the car to the side when braking | |
Jamming of the piston of the wheel brake cylinder Blockage of any steel brake pipe due to a dent or blockage Dirty or oily brake discs, brake drums and brake linings Incorrect adjustment of the brake pressure regulator actuator Faulty brake pressure regulator Wheel alignment misaligned (collapse convergence) Different tire pressure One of the brake circuits does not work (accompanied by a deterioration in braking efficiency and increased brake pedal travel) | Check and eliminate jamming of the piston in the wheel brake cylinder, if necessary, replace damaged parts, bleed the brake system Replace the brake pipe or clean it and bleed the brakes on the car Clean the brake parts Adjust brake pressure regulator actuator Repair or replace brake pressure regulator Adjust wheel alignment (collapse convergence) Set normal tire pressure Replace damaged parts and bleed the brakes |
Increased force on the brake pedal when braking | |
Faulty vacuum brake booster The hose connecting the vacuum booster and the engine intake pipe is damaged, or its fastening on the fittings is loose Swelling of the sealing cuffs of the brake cylinders due to the ingress of gasoline, mineral oils, etc. into the brake fluid. | Replace vacuum brake booster Replace the hose connecting the vacuum booster and the engine intake pipe, or tighten the hose clamps Thoroughly flush the entire brake system, replace the rubber cuffs, pump the brakes on the car |
Squeal or vibration of the brakes | |
Weakening of the return spring of the rear brake pads The appearance of ovality of the brake drums Lubrication of friction brake linings Worn brake linings or inclusion of foreign bodies in them Excessive brake disc runout or uneven wear (felt by the vibration of the brake pedal) | Check the return spring of the rear brake pads, if necessary, replace with a new one Boring the brake drum Scrub the brake linings with a wire brush using warm water and detergent. Eliminate the cause of brake fluid or grease on the brake pads Replace brake pads Grind the brake disc, if the thickness is less than 17.8 mm, replace it |