Brakes and Braking Systems Flashcards

A brake pedal slowly sinks to the floor when held under constant pressure. What is this condition called?

Answer: Brake pedal creep caused by a faulty master cylinder

A worn or damaged master cylinder internal seal allows fluid to bypass under sustained pressure, causing the pedal to slowly sink.

During a DFFT inspection, you find one brake rotor has a blue discoloration. What does this indicate?

Answer: The rotor has been subjected to excessive heat

Blue discoloration on a brake rotor is a sign of overheating, which can alter the metal's hardness and cause the rotor to warp or crack.

A vehicle's parking brake fails to hold the car on a moderate hill. What is the most likely cause on a rear-drum brake vehicle?

Answer: Stretched or corroded parking brake cable

A stretched or corroded cable prevents the parking brake mechanism from applying sufficient force to hold the rear drum shoes against the drum.

After a brake job, a customer returns complaining the brake pedal is very hard to press. What was likely the fault in the repair?

Answer: The brake booster vacuum hose was not reconnected

The brake booster uses engine vacuum to multiply pedal force; without vacuum supply, the driver must overcome hydraulic resistance unassisted, making the pedal feel very hard.

A customer reports the brake pedal vibrates when stopping at highway speed. What is the most likely cause?

Answer: Warped or uneven brake rotors

Warped rotors cause the caliper piston to rapidly advance and retract as the high and low spots pass, creating a pulsating vibration felt through the pedal.

You notice brake fluid is leaking from behind a front wheel. What is the most probable source?

Answer: A leaking brake caliper piston seal

When the caliper piston seal deteriorates, brake fluid bypasses the seal and leaks out, which also reduces hydraulic pressure and braking effectiveness.