How to troubleshoot the brake system failure of automobile maintenance knowledge

①The vacuum hose connector of the brake booster is loose or the hose is leaking.
②The brake shoe or pad is of poor quality.
③The brake shoe is bent or broken.
④The brake caliper is stuck or pulled on the guide pin, and the rear brake shoe is pulled on the supporting base plate.
⑤ Brake caliper, brake cylinder, brake master cylinderpistonSticky or stuck.
⑥The one-way valve of the vacuum booster fails.
⑦The inside of the vacuum booster is stuck.
⑧ The oil return hole of the brake master cylinder is blocked by dirt, and the brake fluid cannot return to the liquid storage tank.
⑨ The brake pipeline is blocked or not smooth.
⑩Use unqualified brake fluid to expand the rubber parts and get stuck in the cylinder hole.

2. Elimination method

①Tighten the connection or replace the leaking hose.
② Replace the brake shoe or pad.
③Replace unqualified brake shoes.
④ Replace the guide pin and bushing, remove the rust and dirt on the rear brake support base plate, or replace the brake base plate.
⑤Check the brake caliper, brake cylinder and brake master cylinder, and replace unqualified parts if necessary.
⑥Steps for checking the one-way valve: start the engine first,Rotating speedIncrease to 1500 rpm, and immediately stop the engine.Wait 2 minutes, then step onBrake pedal. If the number of actions of the vacuum booster is less than twice, it indicates that the one-way valve is damaged.
⑦The method of checking the booster: When the engine is turned off, step on the brake pedal several times to exhaust the vacuum in the system, and then put your foot on the brake pedal to start the engine. If the height of the brake pedal is lowered, the pedal can be kept in the braking position with a smaller pressure, indicating that the vacuum booster system is working normally, otherwise the booster should be replaced.
⑧ Overhaul or replace the brake master cylinder.
⑨ Clean pipeline dirt with compressed air and replace unqualified parts.
⑩ Replace all rubber parts, combination valves and hoses, and use the brake fluid specified by the original factory.