What causes the brake to suddenly become hard and unresponsive while driving?
1 Answers
The reasons and solutions for unresponsive brakes while driving are as follows: 1. Related to braking before engine shutdown: The vehicle's braking system operates at its maximum efficiency only when the engine is running. The brake booster, which amplifies the force applied by the driver to the pedal, is the key component behind vehicle braking. When the engine is off, the brake booster also becomes ineffective, typically depleting its remaining vacuum force after about three pedal presses. In this scenario, the driver simply needs to restart the engine and then attempt to press the brake pedal firmly to reactivate the system. Once the engine is running, the brake booster will resume operation, and the brake pedal will return to normal. 2. Brake booster air leakage or malfunction: If the driver has not pressed the brake pedal after the engine was turned off, or if the brake pedal becomes difficult to press while driving, it is likely due to a faulty brake booster or a leak/blockage in the brake booster vacuum tube. If this issue is detected before driving, the vehicle should not be driven and should be taken to a repair shop immediately. If the problem occurs while driving, remain calm, prioritize slowing down to a stop, and try pressing the pedal multiple times to see if braking can be restored.
