Chrysler Pacifica. Manual - part 447

DIAGNOSIS AND TESTING - BASE BRAKE
SYSTEM

NOTE: There are three diagnosis charts following
that cover the RED BRAKE WARNING INDICATOR
LAMP, BRAKE NOISE and OTHER BRAKE CONDI-
TIONS.

RED BRAKE WARNING INDICATOR LAMP

CONDITION

POSSIBLE CAUSES

CORRECTION

RED BRAKE WARNING
LAMP ON

1. Parking brake lever not fully
released.

1. Release parking brake lever.

2. Parking brake warning lamp
switch on parking brake lever.

2. Inspect and replace switch as necessary.

3. Brake fluid level low in reservoir.

3. Fill reservoir. Check entire system for
leaks. Repair or replace as required.

4. Brake fluid level switch.

4. Disconnect switch wiring connector. If
lamp goes out, replace switch.

5. Mechanical instrument cluster
(MIC) problem.

5. Refer to appropriate Diagnostic
information.

6. Amber ABS Warning Indicator
Lamp also illuminated.

6. Refer to appropriate Diagnostic
information.

BRAKE NOISE

CONDITION

POSSIBLE CAUSES

CORRECTION

CLICK OR SQUAWK ON
PEDAL APPLICATION

1. Brake lamp switch.

1. Replace switch.

2. Brake Transmission Shift Interlock
Linkage.

2. Lubricate BTSI linkage.

3. Pedal pivot bushings

3. Lubricate pivot bushings. Replace if
necessary.

DISC BRAKE CHIRP

1. Excessive brake rotor runout.

1. Follow brake rotor diagnosis and testing.
Correct as necessary.

2. Lack of lubricant on brake caliper
slides.

2. Lubricate brake caliper slides.

3. Caliper/shoes not fully seated.

3. Reseat caliper/shoes.

DISC BRAKE RATTLE OR
CLUNK

1. Broken or missing anti-rattle
spring clips.

1. Replace anti-rattle spring clips.

2. Caliper guide pins/bolts loose.

2. Tighten guide pins/bolts.

DISC BRAKE SQUEAK AT
LOW SPEED (WHILE
APPLYING LIGHT BRAKE
PEDAL EFFORT)

1. Brake shoe linings.

1. Replace brake shoes.

BRAKES - BASE

5 - 3

BRAKES - BASE (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

SCRAPING (METAL-TO-
METAL).

1. Foreign object interference with
brakes.

1. Inspect brakes and remove foreign
object.

2. Brake shoes worn out.

2. Replace brake shoes. Inspect rotors.
Reface or replace as necessary.

OTHER BRAKE CONDITIONS

CONDITION

POSSIBLE CAUSES

CORRECTION

BRAKES CHATTER

1. Disc brake rotor has excessive
thickness variation.

1. Isolate condition as rear or front.
Reface or replace brake rotors as
necessary.

BRAKES DRAG (FRONT
OR ALL)

1. Contaminated brake fluid.

1. Check for swollen seals. Replace all
system components containing rubber.

2. Binding caliper pins or bushings.

2. Replace pins and bushings.

3. Binding master cylinder.

3. Replace master cylinder.

4. Binding brake pedal.

4. Replace brake pedal.

5. Brake lamp switch not adjusted
properly and mounting bracket is
bent.

5. Straighten mounting bracket and
replace brake lamp switch.

BRAKES DRAG (REAR
ONLY)

1. Parking brake cables binding or
froze up.

1. Check cable routing. Replace cables
as necessary.

2. Parking brake cable return spring
not returning shoes.

2. Replace cables as necessary.

3. Rear disc brake parking brake not
properly adjusted.

3. Adjust parking brake shoes.

BRAKES GRAB

1. Contaminated brake shoe linings.

1. Inspect and clean, or replace shoes.
Repair source of contamination.

2. Improper power brake booster
assist.

2. Refer to power brake booster
diagnosis and testing.

EXCESSIVE PEDAL
EFFORT

1. Obstruction of brake pedal.

1. Inspect, remove or move obstruction.

2. Low power brake booster assist
(vacuum leak).

2. Refer to power brake booster
diagnosis and testing.

3. Glazed brake linings.

3. Reface or replace brake rotors as
necessary. Replace brake shoes.

4. Brake shoe lining transfer to brake
rotor.

4. Reface or replace brake rotors as
necessary. Replace brake shoes.

EXCESSIVE PEDAL
TRAVEL (VEHICLE STOPS
OK)

1. Air in brake lines.

1. Bleed brakes.

EXCESSIVE PEDAL
TRAVEL (ONE FRONT
WHEEL LOCKS UP
DURING HARD BRAKING)

1. One of the two hydraulic circuits
to the front brakes is malfunctioning.

1. Inspect system for leaks. Check
master cylinder for internal malfunction.

5 - 4

BRAKES - BASE

BRAKES - BASE (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

PEDAL PULSATES/
SURGES DURING
BRAKING

1. Disc brake rotor has excessive
thickness variation.

1. Isolate condition as rear or front.
Reface or replace brake rotors as
necessary.

PEDAL IS SPONGY

1. Air in brake lines.

1. Bleed brakes.

2. Power brake booster runout
(vacuum assist).

2. Check booster vacuum hose and
engine tune for adequate vacuum
supply. Refer to power brake booster
diagnosis and testing.

PREMATURE REAR
WHEEL LOCKUP

1. Contaminated brake shoe linings.

1. Inspect and clean, or replace shoes.
Repair source of contamination.

2. Inoperative proportioning valve
(non-ABS vehicles).

2. Refer to proportioning valve
diagnosis and testing. Replace valve as
necessary.

3. Improper power brake booster
assist.

3. Refer to power brake booster in the
diagnosis and testing section.

STOP/BRAKE LAMPS
STAY ON

1. Brake lamp switch out of
adjustment.

1. Replace brake lamp switch.

2. Brake pedal binding.

2. Inspect and replace as necessary.

3. Obstruction in pedal linkage.

3. Remove obstruction.

4. Power Brake Booster not allowing
pedal to return completely.

4. Replace power brake booster.

VEHICLE PULLS TO
RIGHT OR LEFT ON
BRAKING

1. Frozen brake caliper piston.

1. Replace frozen piston or caliper.
Bleed brakes.

2. Contaminated brake shoe lining.

2. Inspect and clean, or replace shoes.
Repair source of contamination.

3. Pinched brake lines.

3. Replace pinched line.

4. Leaking piston seal.

4. Replace piston seal or brake caliper.

5. Suspension problem.

5. Refer to the Suspension group.

PARKING BRAKE -
EXCESSIVE LEVER
TRAVEL

1. Rear disc brake parking brake
shoes out of adjustment.

1. Adjust parking brake shoes.

STANDARD PROCEDURE - BASE BRAKE
BLEEDING

NOTE: This bleeding procedure is only for the vehi-
cle’s base brakes hydraulic system. For bleeding
the antilock brakes hydraulic system, (Refer to 5 -
BRAKES - ABS - STANDARD PROCEDURE)

CAUTION: Before removing the master cylinder
cover, thoroughly clean the cover and master cylin-
der fluid reservoir to prevent dirt and other foreign
matter from dropping into the master cylinder fluid
reservoir.

NOTE: The following wheel sequence should be
used when bleeding the brake hydraulic system.
The use of this wheel sequence will ensure ade-
quate removal of all trapped air from the brake
hydraulic system.

• Left Rear Wheel

• Right Front Wheel

• Right Rear Wheel

• Left Front Wheel

BRAKES - BASE

5 - 5

BRAKES - BASE (Continued)

NOTE: When bleeding the brake system, some air
may be trapped in the brake lines or valves far
upstream, as much as ten feet from the bleeder
screw (Fig. 1). Therefore, it is essential to have a
fast flow of a large volume of brake fluid when
bleeding the brakes to ensure all the air gets out.

The brakes may be manually bled or pressure bled.

Refer to the appropriate following procedure.

MANUAL BLEEDING PROCEDURE

NOTE: Correct manual bleeding of the brakes
hydraulic system will require the aid of a helper.

NOTE: To adequately bleed the brakes using the
manual bleeding procedure the rear brakes must be
correctly adjusted. Prior to the manual bleeding of
the brake hydraulic system, correctly adjust the
rear brakes.

(1) Pump the brake pedal three or four times and

hold it down before the bleeder screw is opened.

(2) Push the brake pedal toward the floor and hold

it down. Then open the left rear bleeder screw at
least 1 full turn. When the bleeder screw opens the
brake pedal will drop all the way to the floor.

CAUTION: “Just cracking” the bleeder screw often
restricts fluid flow, allowing only a slow, weak fluid
discharge of fluid. This practice will NOT get all the
air out. Make sure the bleeder is opened at least 1
full turn when bleeding.

(3) Release the brake pedal only after the bleeder

screw is closed.

(4) Repeat steps 1 through 3, four or five times, at

each bleeder screw in the proper sequence. This
should pass a sufficient amount of fluid to expel all
the trapped air from the brake system. Be sure to

monitor the fluid level in the master cylinder, so it
stays at a proper level so air will not enter the brake
system through the master cylinder.

(5) Check pedal travel. If pedal travel is excessive

or has not been improved, enough fluid has not
passed through the system to expel all the trapped
air. Continue to bleed system as necessary.

(6) Perform a final adjustment of the rear brake

shoes (when applicable), then test drive vehicle to be
sure brakes are operating correctly and that pedal is
solid.

PRESSURE BLEEDING PROCEDURE

CAUTION: Use bleeder tank Special Tool C-3496-B
or equivalent with Adapter, Special Tool 6921, to
pressurize the hydraulic system for bleeding.

Follow pressure bleeder manufacturer’s instruc-

tions for use of pressure bleeding equipment.

(1) Install the Adapter Master Cylinder Pressure

Bleed Cap, Special Tool 6921 on the fluid reservoir of
the master cylinder (Fig. 2). Attach the fluid hose
from the pressure bleeder to the fitting on Special
Tool 6921.

(2) Attach a clear plastic hose to the bleeder screw

at one wheel and feed the hose into a clear jar con-
taining fresh brake fluid.

(3) Open the left rear wheel bleeder screw at least

one full turn or more to obtain an adequate flow of
brake fluid.

Fig. 1 Trapped Air In Brake Fluid Line

1 - TRAPPED AIR

Fig. 2 Tool 6921 Installed On Master Cylinder

1 - SPECIAL TOOL 6921
2 - FLUID RESERVOIR

5 - 6

BRAKES - BASE

BRAKES - BASE (Continued)

Content .. 445 446 447 448 ..