Question 3748
If your passenger car has a brake booster, what happens when the engine is off and the ignition is switched off?
- You will have to apply more pressure to the brake pedal if you want to brake.
- The wheels lock up.
- You will have to pull the parking brake tighter.
Show answer and explanation
Correct answer: You will have to apply more pressure to the brake pedal if you want to brake.
The brake booster multiplies the force you apply with your foot when braking. It uses the vacuum created by the running engine, so when the engine is off and the ignition is switched off, it stops helping you. The brakes still work, but the pedal gets hard and you have to press it much harder to get the same braking effect. This does not lock the wheels, and the parking brake does not depend on the brake booster.