Manitoba Airbrake Practice Exam

When testing brake performance, it's considered a major defect if:

1. The service brakes fail to stop the vehicle

2. The spring brakes fail to hold the vehicle in place

3. Both A and B

4. The brake lights do not function

The correct answer is: Both A and B

When testing brake performance, a major defect is considered when both the service brakes fail to stop the vehicle and the spring brakes fail to hold the vehicle in place simultaneously. This means that option A alone would not be a major defect as long as the spring brakes are working properly. Option B alone would also not be a major defect if the service brakes are functional. Option D, although it is important for brake safety, is not a major defect in this context as it does not directly affect the vehicle's ability to stop or hold in place. Therefore, the correct answer is C.