Why does the brake suddenly become hard and unpressable while driving?

[WilliamLynn]

The reasons why the brake suddenly becomes hard and unpressable while driving are: 1. The owner stepped on the brake several times after turning off the engine, causing the vacuum in the brake booster pump to disappear. Simply restart the engine and press the brake pedal firmly, and it will return to normal after starting; 2. There is air leakage or component failure in the vehicle's brake booster pump. You can find a nearby repair shop to clear the fault before continuing to drive. The correct braking methods are: 1. When driving at low speed, emergency braking can be applied by stepping on the brake pedal firmly if there is a sudden event ahead, but this should not be done at high speed to avoid vehicle skidding or rollover; 2. In situations where long downhill slopes in mountainous areas or continuous braking may cause high temperatures, intermittent braking by alternately pressing and releasing the brake pedal can effectively prevent the braking system from overheating.