Which of the following are functions of a typical hydraulic brake system combination valve?

A) delays application of front disc brakes
B) reduces rear wheel lock-up
C) alerts the driver to a partial circuit hydraulic failure
D) all of the above

Combination Valve

Used in a hydraulic brake system, it contains the safety switch, metering, and proportioning valves in a single valve body and usually is located close to the master cylinder. Also may refer to other multiple function valves such as the service, emergency, relay valve (SERV) used on air brake systems.

Hydraulic Brake System

A system in vehicles that uses fluid pressure to operate the brakes.

Rear Wheel Lock-up

A condition in braking where the rear wheels of a vehicle stop rotating and skid, often due to excessive brake force or poor road conditions.