✓ TradeExamPro

TradeExamPro › Automotive › Hybrid and electric vehicles

Braking diagnosis practice questions

23 questions from the hybrid and electric vehicles practice test.

Braking diagnosis practice test

10 questions, graded as you go, with the reason for every answer. No sign-up.

What this covers

Sample questions

What happens to regenerative braking when the battery is fully charged?

  1. It is reduced and friction brakes do more
  2. It gets stronger to burn off energy
  3. It continues and charges the 12 V battery
  4. It is unchanged at any state of charge
Show the answer

A. It is reduced and friction brakes do more

A full battery has nowhere to put the energy, so the controller cuts regeneration and makes up the difference hydraulically. Drivers notice it on a long downhill after a full charge.

Reference: Regenerative braking limits

What is brake blending?

  1. Mixing two types of brake fluid in the reservoir
  2. Applying the front and rear brakes at different times
  3. Pulsing the brakes to stop wheel lockup
  4. Splitting braking demand between motor and hydraulics
Show the answer

D. Splitting braking demand between motor and hydraulics

The brake controller works out the driver's request, takes what regeneration can supply and adds hydraulic pressure for the rest. Pulsing to stop lockup is ABS.

Reference: Regenerative brake blending

What does the pedal stroke simulator do in a hybrid brake system?

  1. Measures the pad wear at each wheel
  2. Boosts pedal pressure using stored engine vacuum
  3. Gives normal pedal feel while regenerating
  4. Charges the brake accumulator
Show the answer

C. Gives normal pedal feel while regenerating

In normal stops the pedal is isolated from the wheel circuits, so a spring-loaded simulator gives the driver a natural feel. Vacuum is unreliable on a hybrid because the engine is often off.

Reference: Hybrid brake-by-wire operation

Other topics