Master Cylinder; Brake Pedal - Chrysler 2000 LHS Owner's Manual

5 - 2 BRAKES
DESCRIPTION AND OPERATION
BASE BRAKE SYSTEM
DESCRIPTION
The base brake system consists of the following
components:

• brake pedal

• master cylinder

• power brake booster
• brake tubes and hoses
• proportioning valves (2)
• disc brakes (front and rear)
• brake lamp switch
• brake fluid level switch
• parking brakes
All brakes are power assist type through the use of
a vacuum operated power brake booster.
The hydraulic brake system is diagonally split on
both the non-antilock and antilock braking systems.
This means the left front and right rear brakes are
on one hydraulic circuit from the master cylinder and
the right front and left rear are on the other.
Front disc brakes control the braking of the front
wheels; rear braking is controlled by rear disc
brakes.
Vehicles equipped with the optional antilock brake
system (ABS) (with and without traction control) use
a system designated Mark 20i. This system shares
most base brake hardware used on vehicles without
ABS. All components differing from the base brake
hardware are described in detail in the ANTILOCK
BRAKE SYSTEM section in this group of the service
manual.
The parking brake on this vehicle is pedal-oper-
ated.
For more information on the description of any
individual base brake component, refer to that com-
ponent elsewhere in this section.
OPERATION
When a vehicle needs to be stopped, the driver
applies the brake pedal. The brake pedal pushes the
input rod of the power brake booster into the booster.
The booster uses vacuum to ease pedal effort as force
is transferred through the booster to the master cyl-
inder. The booster's output rod pushes in the master
cylinder's primary and secondary pistons applying
hydraulic pressure through the chassis brake tubes,
junction block, and proportioning valves to the
brakes at each tire and wheel assembly.
The pedal-operated parking brake operates in the
following manner. When applied, the parking brake
lever pulls on cables that actuate parking brake
shoes at each rear wheel.
For more information on the operation of any indi-
vidual base brake component, refer to that compo-
nent elsewhere in this section.
BRAKE PEDAL
DESCRIPTION
A suspended type brake pedal is used on this vehi-
cle (Fig. 1). The pedal pivots on a shaft mounted in
the pedal support bracket under the instrument
panel. The pedal also connects to the power brake
booster input rod. The pedal ratio is 3.18:1.
Fig. 1 Brake Pedal
1 – BUSHINGS
2 – BRAKE PEDAL
3 – BRAKE LAMP SWITCH
4 – PIVOT SHAFT
OPERATION
When the brake pedal is depressed, it pushes in on
the power brake booster input rod applying the
brakes. At the same time, it allows the brake lamp
switch's plunger to extend, thus applying the brake
lamps.
MASTER CYLINDER
DESCRIPTION
One style master cylinder is used for all applica-
tions. A Bosch center-valve master cylinder is used
(Fig. 2). It has the brake fluid reservoir mounted on
top and the brake fluid level switch is mounted in
the side of that reservoir.
OPERATION
When the brake pedal is pressed, the master cylin-
der primary and secondary pistons apply brake pres-
sure through the
proportioning valves to each brake assembly. The
chassis brake tubes
LH
and