Chrysler Concorde 2004 Service Manual page 1512

5 - 46 BRAKES - BASE BRAKE SYSTEM
POWER BRAKE BOOSTER (Continued)
(6) Install and tighten the 2 master cylinder to
booster mounting nuts (Fig. 78) to 28 N·m (250 in.
lbs.) torque.
(7) Reconnect brake fluid level sensor connector.
(8) Connect all vacuum hoses onto the booster vac-
uum check valve.
(9) Check brake lamp switch operation.
(10) Install the wiper module reinforcement on the
vehicle (Fig. 77). Install the 8 bolts, attaching the
reinforcement to the strut towers. Install the bolt
attaching the wiper module to the reinforcement.
(11) Install the covers over the wiper module and
the cowl (Fig. 76). Install and securely tighten the
attaching screws.
(12) Reconnect the battery ground cable to the
ground stud on the shock tower.
(13) Turn windshield wipers ON, then OFF, in
order to park wipers in the proper position before
installing wiper arms.
(14) Install the wiper arms on the pivots (Fig. 75).
Install and securely tighten the wiper arm to pivot
attaching nuts. Install the caps on the wiper arms
covering the pivot nuts.
(15) Verify proper operation of the power brake
booster and brake system.
PROPORTIONING VALVE
DESCRIPTION
Two proportioning valves are used on each vehicle
without antilock brakes. One valve is used for each
rear brake hydraulic circuit. The proportioning
valves that are located in the junction block (Refer to
5 - BRAKES - BASE/HYDRAULIC/MECHANICAL/
JUNCTION BLOCK - DESCRIPTION). The valves
are not serviceable and must be replaced as part of
the junction block.
OPERATION
Proportioning valves balance front to rear braking
by controlling (at a given ratio) brake hydraulic pres-
sure to the rear brakes above a preset level (split
point). On light pedal applications equal brake pres-
sure is transmitted to both the front and rear brakes.
On heavier pedal applications, through the use of
proportioning valves, the pressure transmitted to the
rear will be lower than the front brakes. This pre-
vents premature rear wheel skid.
If hydraulic pressure is lost in one-half of the diag-
onally split brake hydraulic system, the operation of
the proportioning valve in the remaining half is not
affected.
DIAGNOSIS AND TESTING - PROPORTIONING
VALVE
Vehicles without Antilock Brakes have two propor-
tioning valves. One proportioning valve controls the
right rear brake, and the other proportioning valve
controls the left rear brake. The proportioning valves
are located in the junction block. Vehicle's with ABS
do not have proportioning valves to test, they use
Electronic Variable Brake Proportioning which is
built into the Integrated Control Unit (ICU).
If premature wheel skid occurs on a hard brake
application, it could be an indication that a malfunc-
tion has occurred with one of the two rear brake pro-
portioning valves. Test the valve that controls the
side of the vehicle on which the skid occurs. Both
proportioning valves have the same pressure specifi-
cations and are tested in the same way.
(1) If the left rear proportioning valve is suspect,
disconnect the tube nut fitting at the master cylinder
primary port (port closest to power brake booster).
Install Adapter, Special Tool 8494-2, in its place on
the master cylinder.
(2) If the right rear proportioning valve is suspect,
disconnect the tube nut fitting at the master cylinder
secondary port (port furthest from power brake boost-
er). Install Adapter, Special Tool 8494-2, in its place
on the master cylinder.
(3) Connect primary brake tube to Adapter.
(4) Install a Pressure
C-4007-A, to the Adapter.
(5) Tighten all tube nut fittings to 17 N·m (145 in.
lbs.) torque.
(6) Remove screw fastening the speed control servo
to the upper radiator closure panel (Fig. 81).
(7) Remove screw fastening the washer filler tube
to the upper radiator closure panel (Fig. 81).
Fig. 81 Servo And Filler Tube Fasteners
1 - SPEED CONTROL SERVO
2 - WINDSHIED WASHER FILLER TUBE
3 - SCREW
4 - SCREW
LH
Gauge, Special Tool