Brake Master Cylinder: Description and Operation

Brake Master Cylinder

The brake master cylinder is a dual piston type. The brake master cylinder operates as follows:
^ When the brake pedal is pressed, pressure is applied by mechanical linkage to the primary and secondary piston.
^ Brake master cylinder pistons apply hydraulic pressure to the 2 diagonal hydraulic circuits.
^ The anti-lock brake system (ABS) brake master cylinder cannot be overhauled, due to internal adjustments which require extensive special tools and fixtures. The repair is made by installing a new master cylinder only.

The brake master cylinder consists of:
^ brake master cylinder fluid reservoir
^ brake master cylinder body

Brake Master Cylinder Reservoir

NOTE: The brake master cylinder body and brake master cylinder reservoir are replaced as an assembly. The reservoir cannot be replaced separately from the brake master cylinder body.

The brake master cylinder reservoir:
^ is mounted to the brake master cylinder body.
^ holds fluid supply for each brake master cylinder hydraulic circuit.
^ provides visual maximum and minimum fluid level markings.
^ contains the brake master cylinder fluid level indicator switch.

The brake master cylinder fluid level indicator switch can be checked by putting a magnetic probe against the inside of the reservoir to activate the indicator switch.