I assume you are referring to the 3 outlet ports? Thereare 2 separateones for the front brakes, one for the left front brake and one for the right front,and the 3rd goes to the rear brakes. There are 2 hoses from the fluid reservoir and 2 more on the bottom which have electrical connections, the brake light switch and the warning light switch.
pray!
The bigger one for your discs.
A fast-fill valve in a master cylinder acts as the inlet port and the compensating port. fitted between the reservoir and the cylinder bore. It is a combination valve with a ball and a pressure seal. Depending on the pressure, it allows flid to flow from the large bore of the cylinder to the reservoir, or from the reservoir into the large bore.
Assist in the rapid return of the brake pedal when it is released
. If you have the 4-port master cylinder, the bottom ports go to the rear brakes & the upper side ports go to the front brakes.
If a pressure type brake fluid dispenser is available attach it to the top of the master cylinder. Other wise fill the master cylinder, start with the wheel cylinder that is furthermost from the master, and bleed until fluid comes out clean and free from bubbles. make sure to replenish the the master cylinder as needed. then proceed to the next farther wheel cylinder and repeat with the rest of the wheel cylinders. top off the master cylinder. Test with the engine off then with the engine running before driving.
the master cylinder is designed so that when the brakes are applied, the pistons (primary and secondary) closes the compensating port and opens intake port. this allows brake pressure to be formed in brake system to apply brakes and allows brake fluid to fill behind pistons (through intake ports) when you release the brakes, the primary and secondary piston springs push their pistons (inside the master cylinder) to its rest position, faster than fluid can fill the chambers. this causes the brake fluid to flow past the piston cups (this happens when the rubber cup flexes foward) as the pistons pass the compensating port, brake fluid is allowed to return to the master cylinder reservoir. the intake and compensating ports act as a breather for the master cylinder. hope this answers your queston :)
The 2002 Volkswagon Beetle OBD 2 port is under dash at left side
The 2002 Volkswagon Beetle OBD 2 port is under dash at left side
The low side charging port is located high up, near the firewall, on the driver's side, right by the brake master cylinder.
where is the diagnostic port on a 2001 vw bug
Located next to the break master cylinder on the drivers side. in the engine compartment.