The brake master cylinder is a dual-piston type. It is assisted by the power brake booster.
The following conditions are considered normal and are not indications that the brake master cylinder is in need of repair or replacement:
Low brake fluid level is detected without signs of leakage. This condition is caused by displacement of brake fluid from the brake master cylinder reservoir into the disc brake caliper, rear disc brake caliper, or rear wheel cylinders to compensate for normal brake wear. Add brake fluid as needed.
A momentary or slight squirt of brake fluid from the brake master cylinder reservoir upon application of the brake pedal.
A trace of fluid found on the outside of the power brake booster below the brake master cylinder mounting flange. This condition results from the lubricating action of the brake master cylinder wiping seal.
