2003 CHRYSLER CARAVAN check engine

CONDITION POSSIBLE CAUSES CORRECTION
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.
PEDAL PULSATES/
SURGES DURING
BRAKING1. Rear brake drum out of round or
disc brake rotor has excessive
thickness variation.1. Isolate condition as rear or front.
Reface or replace brake drums or
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 LOCKUP1. 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
S TAY O N1. 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
BRAKING1. 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 HANDLE
TRAVEL1. Rear drum brakes or rear disc
brake parking brake shoes out of
adjustment.1. Adjust rear drum brake shoes, or
rear parking brake shoes on vehicles
with rear disc brakes.
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.
RSBRAKES - BASE5-7
BRAKES - BASE (Continued)
ProCarManuals.com

The power brake booster can be identified by the
tag attached to the body of the booster (Fig. 57). This
tag contains the production part number, the date it
was built, and who the manufacturer of the power
brake booster is.
NOTE: The power brake booster assembly is not a
repairable component and must be replaced as a
complete assembly if found to be faulty in any way.
The check valve located on the power brake
booster face is not repairable, but it can be
replaced separately from the power brake booster.
The different engine combinations used in this
vehicle require different vacuum hose routings to the
power brake booster. All vacuum hoses must be
routed from the engine to the power brake booster
without kinks or excessively tight bends.
OPERATION
The power brake booster reduces the amount of
force required by the driver to obtain the necessary
hydraulic pressure to stop a vehicle.
The power brake booster is vacuum operated. The
vacuum is supplied from the intake manifold on the
engine through a vacuum hose and the power brake
booster check valve (Fig. 56).As the brake pedal is depressed, the power brake
booster's input rod moves forward (Fig. 56). This
opens and closes valves in the power booster allowing
atmospheric pressure to enter on one side of a dia-
phragm. Engine vacuum is always present on the
other side. This difference in pressure forces the out-
put rod of the power brake booster out against the
primary piston of the master cylinder. As the pistons
in the master cylinder move forward this creates the
hydraulic pressure in the brake system.
DIAGNOSIS AND TESTING - POWER BRAKE
BOOSTER
BASIC TEST
(1) With engine off, depress and release the brake
pedal several times to purge all vacuum from the
power brake booster.
(2) Depress and hold the pedal with light effort (15
to 25 lbs. pressure), then start the engine.
The pedal should fall slightly, then hold. Less effort
should be needed to apply the pedal at this time. If
the pedal fell as indicated, perform the VACUUM
LEAK TEST listed after the BASIC TEST. If the
pedal did not fall, continue on with this BASIC
TEST.
(3) Disconnect the vacuum hose on the vacuum
check valve, then place a vacuum gauge in line
between the vacuum hose and the valve.
(4) Start the engine.
(5) When the engine is at warm operating temper-
ature, allow it to idle and check the vacuum at the
gauge.
Fig. 56 Power Brake Booster (Typical)
1 - VACUUM CHECK VALVE
2 - POWER BRAKE BOOSTER ASSEMBLY
3 - INPUT ROD
4 - POWER BOOSTER ASSEMBLY TO DASH PANEL MOUNTING
STUDS (4)
5 - MASTER CYLINDER MOUNTING STUDS (2)
6 - OUTPUT ROD
Fig. 57 MASTER CYLINDER AND BOOSTER
1 - POWER BRAKE BOOSTER
2 - BOOSTER IDENTIFICATION LABEL
3 - FLUID LEVEL SWITCH CONNECTOR
4 - PRIMARY BRAKE TUBE NUT
5 - SECONDARY BRAKE TUBE NUT
6 - MASTER CYLINDER
RSBRAKES - BASE5-41
POWER BRAKE BOOSTER (Continued)
ProCarManuals.com

If the vacuum supply is 12 inches Hg (40.5 kPa) or
more, the power brake booster is defective and must
be replaced. If the vacuum supply is below 12 inches
Hg, continue on with this BASIC TEST.
(6) Shut off the engine.
(7) Connect the vacuum gauge to the vacuum ref-
erence port on the engine intake manifold.
(8) Start the engine and observe the vacuum
gauge.
If the vacuum is still low, check the engine tune
and repair as necessary. If the vacuum is above 12
inches Hg, the hose or check valve to the booster has
a restriction or leak.
Once an adequate vacuum supply is obtained,
repeat the BASIC TEST.
VACUUM LEAK TEST
(1) Disconnect the vacuum hose on the vacuum
check valve, then place a vacuum gauge in line
between the vacuum hose and the valve.
(2) Start the engine.
(3) Allow the engine to warm up to normal operat-
ing temperature and engine idle.
(4) Using vacuum line pliers, close off the vacuum
supply hose near the booster, but before the vacuum
gauge, then observe the vacuum gauge.
If the vacuum drop exceeds 1.0 inch Hg (3.3 kPa)
in one minute, repeat the above steps to confirm the
reading. The vacuum loss should be less than 1.0
inch Hg in one minute time span. If the loss is more
than 1.0 inch Hg, replace the power brake booster. If
it is not, continue on with this test.
(5) Remove the pliers from the hose temporarily.
(6) Apply light effort (approximately 15 lbs. of
force) to the brake pedal and hold the pedal steady.
Do not move the pedal once the pressure is applied
or the test results may vary.
(7) Have an assistant reattach the vacuum line
pliers to the vacuum supply hose.
(8) Allow 5 seconds for stabilization, then observe
the vacuum gauge.
If the vacuum drop exceeds 3.0 inches Hg (10 kPa)
in 15 seconds, repeat the above steps to confirm the
reading. The vacuum loss should be less than 3.0
inches Hg in 15 seconds time span. If the loss is
more than 3.0 inches Hg, replace the power brake
booster. If it is not, the booster is not defective.
(9) Remove the pliers and vacuum gauge.
REMOVAL
REMOVAL - LHD
CAUTION: Reserve vacuum in power brake booster
must be pumped down (removed) before removing
master cylinder from booster. This is necessary toprevent booster from sucking in any contamination
as master cylinder is removed. This can be done
simply by pumping the brake pedal, with the vehi-
cle's engine not running, until a firm feeling brake
pedal is achieved.
(1) With engine not running, pump the brake
pedal until a firm pedal is achieved (4-5 strokes).
(2) Remove negative battery cable terminal from
battery.
(3) Remove positive battery cable terminal from
battery.
(4) Remove battery thermal guard shield.
(5) Remove battery clamp, nut and battery from
the battery tray.
(6) Remove screw securing engine coolant filler
tube to battery tray.
(7) If the vehicle is equipped with speed control,
disconnect the vacuum hose at the vacuum tank built
into the battery tray.
(8) Remove the two nuts and one bolt securing bat-
tery tray in place. Remove battery tray.
(9) If vehicle is equipped with speed control:
(a) Disconnect wiring harness connector from
the speed control servo.
(b) Remove the two servo mounting nuts.
(c) Lay speed control servo off to the side, out of
the way.
(10) Remove the wiper module (unit). (Refer to 8 -
ELECTRICAL/WIPERS/WASHERS/WIPER MOD-
ULE - REMOVAL)
(11) Disconnect wiring harness connector from
brake fluid level switch in master cylinder fluid res-
ervoir (Fig. 58).
Fig. 58 Master Cylinder And Booster
1 - POWER BRAKE BOOSTER
2 - BOOSTER IDENTIFICATION LABEL
3 - FLUID LEVEL SWITCH CONNECTOR
4 - PRIMARY BRAKE TUBE NUT
5 - SECONDARY BRAKE TUBE NUT
6 - MASTER CYLINDER
5 - 42 BRAKES - BASERS
POWER BRAKE BOOSTER (Continued)
ProCarManuals.com

CAUTION: Before removing the master cylinder
from the power brake vacuum booster, the master
cylinder and vacuum booster must be thoroughly
cleaned. This must be done to prevent dirt particles
from falling into the power brake vacuum booster.
(12) Clean area where master cylinder assembly
attaches to power brake booster. Use only a solvent
such as MopartBrake Parts Cleaner or equivalent.
(13) Disconnect primary and secondary brake
tubes from ABS integrated control unit or non-ABS
junction block (Fig. 59). Install sealing plugs in the
now open brake tube ports and install caps on ends
of tubes.
NOTE: It is not necessary to remove the brake
tubes from the master cylinder when removing the
master cylinder from the vacuum booster.
(14) Remove two nuts attaching master cylinder to
power brake booster (Fig. 59).
(15) Slide master cylinder straight out of power
brake booster. Remove master cylinder with primary
and secondary tubes from vehicle.
CAUTION: A seal on the rear of the master cylinder
is used to create the seal for holding vacuum in the
power brake vacuum booster. The vacuum seal on
the master cylinder MUST be replaced whenever the
master cylinder is removed from the power brake
vacuum booster.
(16) Disconnect vacuum hose from check valve
located on vacuum booster.DO NOT REMOVE
CHECK VALVE FROM POWER BRAKE
BOOSTER.(17) Inside vehicle, remove silencer panel under
instrument panel below steering column.
(18) Locate the booster input rod to brake pedal
connection under the instrument panel. Position a
small screwdriver between the center tang on the
power brake booster input rod to brake pedal pin
retaining clip (Fig. 60).
(19) Rotate screwdriver enough to allow retaining
clip center tang to pass over end of brake pedal pin.
Then pull retaining clip off brake pedal pin.Discard
retaining clip. It is not to be reused. Replace
only with a new retaining clip when assem-
bling.
(20) Slide booster input rod off pedal pin.
(21) Remove the four nuts attaching power brake
booster to dash panel (Fig. 61).
(22) Slide power brake booster forward and remove
through engine compartment (Fig. 62).
CAUTION: Do not attempt to disassemble the power
brake vacuum booster. It is serviced ONLY as a
complete assembly.
REMOVAL - RHD
CAUTION: Reserve vacuum in power brake booster
must be pumped down (removed) before removing
master cylinder from booster. This is necessary to
prevent booster from sucking in any contamination
as master cylinder is removed. This can be done
simply by pumping the brake pedal, with the vehi-
cle's engine not running, until a firm feeling brake
pedal is achieved.
Fig. 59 Master Cylinder Mounting
1 - MASTER CYLINDER MOUNTING NUTS
2 - MASTER CYLINDER
3 - SECONDARY TUBE NUT AT ICU
4 - PRIMARY TUBE NUT AT ICU
Fig. 60 Vacuum Booster Input Rod Retaining Pin
1 - BRAKE PEDAL
2 - INPUT ROD
3 - SCREWDRIVER
4 - RETAINING CLIP
5 - BRAKE PEDAL PIN
RSBRAKES - BASE5-43
POWER BRAKE BOOSTER (Continued)
ProCarManuals.com

CAUTION: A seal on the rear of the master cylinder
is used to create the seal for holding vacuum in the
power brake vacuum booster. The vacuum seal on
the master cylinder MUST be replaced whenever the
master cylinder is removed from the power brake
vacuum booster.
(14) Disconnect vacuum hose from check valve
located on booster.DO NOT REMOVE CHECK
VALVE FROM POWER BRAKE BOOSTER.
(15) Under the instrument panel, remove booster
input rod trim cover.
(16) Locate the booster input rod to brake pedal
torque shaft connection under the instrument panel.
Position a small screwdriver between the center tang
on the retaining clip (Fig. 65).
(17) Rotate screwdriver enough to allow retaining
clip center tang to pass over end of brake pedal pin.
Then pull retaining clip off brake pedal torque shaft
pin.Discard retaining clip. It is not to be
reused. Replace only with a new retaining clip
when assembling.
(18) Remove booster input rod from pedal torque
shaft pin.
(19) Remove the three easily accessed mounting
nuts attaching power brake booster to dash panel
and loosen fourth (Fig. 66). As fourth nut is loosened,
push the booster forward periodically until the nut
can be completely removed.
(20) Slide power brake booster forward and remove
through engine compartment (Fig. 67).
CAUTION: Do not attempt to disassemble the power
brake vacuum booster. It is serviced ONLY as a
complete assembly.
Fig. 64 RHD Master Cylinder Mounting
1 - PRIMARY BRAKE TUBE NUT
2 - SECONDARY BRAKE TUBE NUT
3 - MASTER CYLINDER MOUNTING NUTS
Fig. 65 Booster Input Rod Pin Retaining Clip
(Typical)
1 - BRAKE PEDAL
2 - INPUT ROD
3 - SCREWDRIVER
4 - RETAINING CLIP
5 - BRAKE PEDAL PIN
Fig. 66 Booster, Torque Shaft And Pedal Mounting
1 - PEDAL MOUNTING NUT
2 - BRAKE PEDAL ASSEMBLY
3 - PEDAL MOUNTING NUT
4 - PEDAL TORQUE SHAFT
5 - BOOSTER MOUNTING NUT
6 - BOOSTER BRACKET
7 - POWER BRAKE BOOSTER
8 - BOOSTER BRACKET MOUNTING NUT
RSBRAKES - BASE5-45
POWER BRAKE BOOSTER (Continued)
ProCarManuals.com

the mounting nuts to a torque of 14 N´m (124 in.
lbs.).
(16) Install the battery tray. Install the two nuts
and one bolt attaching the battery tray to the vehicle.
Tighten the bolt and nuts to a torque of 14 N´m (124
in. lbs.).
(17) If vehicle is equipped with speed control, con-
nect the servo vacuum hose to the vacuum tank on
the battery tray.
(18) Install the air inlet resonator and hoses as an
assembly on the throttle body and air cleaner hous-
ing. Securely tighten hose clamp at air cleaner hous-
ing and throttle body.
(19) Secure the engine coolant filler neck to the
battery tray with its mounting screw.
(20) Install the battery, clamp and mounting nut.
(21) Install the positive battery cable on the bat-
tery.
(22) Install the negative battery cable on the bat-
tery.
(23) Install the battery thermal guard shield.
(24) Bleed the base brakes as necessary. (Refer to
5 - BRAKES - STANDARD PROCEDURE)
(25) Road test vehicle to ensure operation of the
brakes.
INSTALLATION - RHD
(1) Position power brake booster on dash panel
using the reverse procedure of its removal (Fig. 67).
(2) Below instrument panel, first install the two
upper nuts mounting the booster to the dash panel,
drawing it into place, then install the two lower
mounting nuts. Tighten the mounting nuts to a
torque of 29 N´m (250 in. lbs.).
(3) Using lubriplate, or equivalent, coat the sur-
face of the brake pedal torque shaft pin where it con-
tacts the booster input rod.CAUTION: When installing the brake pedal torque
shaft pin on the power brake booster input rod, do
not re-use the old retaining clip.
(4) Install booster input rod on brake pedal torque
shaft pin and install a NEW retaining clip (Fig. 70).
(5) Install booster input rod trim cover.
(6) Connect vacuum hose to check valve on power
brake booster.
CAUTION: The master cylinder (and its rear seal) is
used to create the seal for holding vacuum in the
vacuum booster. The vacuum seal on the master
cylinder MUST be replaced with a NEW seal when-
ever the master cylinder is removed from the vac-
uum booster.
CAUTION: When removing the vacuum seal from
the master cylinder, do not use a sharp tool.
(7) Using a soft tool such as a trim stick, remove
the vacuum seal from the master cylinder mounting
flange.
(8) Install a NEW vacuum seal on rear mounting
flange of the master cylinder (Fig. 71).
(9) Position master cylinder on studs of booster,
aligning push rod on booster with master cylinder
piston.
(10) Install the two nuts mounting the master cyl-
inder to the booster (Fig. 64). Tighten both mounting
nuts to a torque of 25 N´m (225 in. lbs.).
(11) Connect wiring harness connector to brake
fluid level switch in the master cylinder fluid reser-
voir (Fig. 63).
Fig. 69 Vacuum Seal (Typical)
1 - MASTER CYLINDER ASSEMBLY
2 - VACUUM SEAL
Fig. 70 Retaining Pin Installed On Brake Pedal Pin
(Typical)
1 - BRAKE PEDAL
2 - RETAINING CLIP
3 - BOOSTER INPUT ROD
RSBRAKES - BASE5-47
POWER BRAKE BOOSTER (Continued)
ProCarManuals.com

SERVICE DIAGNOSIS - CLUTCH GRAB/CHATTER
CONDITION POSSIBLE CAUSES CORRECTION
CLUTCH DISC FACING
COVERED WITH OIL OR
GREASEOil leak at engine rear main or
transaxle input shaft seal.Correct leak and replace modular clutch
assembly (2.4L Gas) or clutch cover and disc
(2.5L TD).
Too much grease applied to splines
of disc and input shaft.Apply lighter coating of grease to splines.
NO FAULT FOUND WITH
CLUTCH
COMPONENTSProblem actually related to
suspension or driveline component.Further diagnosis required. Check engine/
transmission mounts, suspension attaching
parts and other driveline components as
needed.
Engine related problems. Check EFI and ignition systems.
PARTIAL ENGAGEMENT
OF CLUTCH DISCClutch cover, spring, or release
fingers bent, distorted (rough
handling, improper assembly).Replace modular clutch assembly (2.4L Gas)
or clutch cover and disc (2.5L TD).
Clutch disc damaged or distorted. Replace modular clutch assembly (2.4L Gas)
or clutch cover and disc (2.5L TD).
Clutch misalignment. Verify modular clutch pilot plate alignment to
crankshaft. Replace the modular clutch
assembly (2.4L Gas) or clutch cover and disc
(2.5L TD) if the pilot plate is loose or bent.
Improper transaxle-to-engine
installation.Verify transaxle is properly installed to
engine.
SERVICE DIAGNOSIS - CLUTCH SLIPS
CONDITION POSSIBLE CAUSES CORRECTION
DISC FACING WORN
OUTNormal wear. Replace modular clutch assembly (2.4L Gas)
or clutch cover and disc (2.5L TD).
Driver frequently rides (slips) clutch,
results in rapid wear, overheating.Replace modular clutch assembly (2.4L Gas)
or clutch cover and disc (2.5L TD).
Insufficient clutch cover diaphragm
spring tensionReplace modular clutch assembly (2.4L Gas)
or clutch cover and disc (2.5L TD).
CLUTCH DISC FACING
CONTAMINATED WITH
OIL OR GREASELeak at rear main oil seal or
transaxle input shaft sealReplace leaking seals. Replace modular
clutch assembly (2.4L Gas) or clutch cover
and disc (2.5L TD).
Excessive amount of grease applied
to input shaft splinesApply less grease to input shaft. Replace
modular clutch assembly (2.4L Gas) or clutch
cover and disc (2.5L TD).
Road splash, water entering housing Seal housing. Inspect clutch assembly.
CLUTCH IS RUNNING
PARTIALLY
DISENGAGEDRelease bearing sticking or binding,
does not return to normal running
position.Verify that bearing is actually binding. Then,
replace bearing and transmission front
bearing retainer if sleeve surface is
damaged.
Clutch pedal not returning to static
position.Inspect pedal assembly for damage and/or
obstructions. Replace componnents as
necessary.
Clutch master cylinder or pushrod
damaged causing high preload.Replace clutch master cylinder assembly.
Slave cylinder binding or stuck. Replace slave cylinder.
6 - 4 CLUTCHRS
CLUTCH (Continued)
ProCarManuals.com

DIAGNOSIS AND TESTING - DRIVE PLATE
MISALIGNMENT
Common causes of misalignment are:
²Heat warping
²Mounting drive plate on a dirty crankshaft
flange
²Incorrect bolt tightening
²Improper seating on the crankshaft shoulder
²Loose crankshaft bolts
Clean the crankshaft flange before mounting the
drive plate. Dirt and grease on the flange surface
may misalign the flywheel, causing excessive runout.
Use new bolts when mounting drive plate to crank-
shaft. Tighten drive plate bolts to specified torque
only. Over-tightening can distort the drive plate hub
causing excessive runout.
DIAGNOSIS AND TESTING - CLUTCH COVER
AND DISC RUNOUT
Check condition of the clutch cover before installa-
tion. A warped cover or diaphragm spring will cause
grab and/or incomplete release or engagement. Use
care when handling the clutch assembly. Impact can
distort the cover, diaphragm spring, and release fin-
gers.
DIAGNOSIS AND TESTING - CLUTCH CHATTER
COMPLAINTS
For all clutch chatter complaints, perform the fol-
lowing:
(1) Check for loose, misaligned, or broken engine
and transmission mounts. If present, they should be
corrected at this time. Test vehicle for chatter. If
chatter is gone, there is no need to go any further.
(2) If chatter persists, check hydraulic clutch
release system is functioning properly.
(3) Check for loose connections in drivetrain. Cor-
rect any problems and determine if clutch chatter
complaints have been satisfied. If not:
(a) Remove transaxle.
(b) Check to see if the release bearing is sticky
or binding. Replace bearing, if needed.
(c) Check linkage for excessive wear on the pivot
stud and fork fingers. Replace all worn parts.
(d) Check clutch assembly for contamination
(dirt, oil). Replace clutch assembly, if required.
(e) Check to see if the clutch disc hub splines
are damaged. Replace with new clutch assembly, if
necessary.
(f) Check input shaft splines for damage.
Replace, if necessary.
(g) Check for uneven wear on clutch fingers.
(h) Check for broken clutch cover diaphragm
spring fingers. Replace with new clutch assembly,
if necessary.
SPECIAL TOOLS - T850 TRANSAXLE
CLUTCH RELEASE LEVER AND
BEARING
REMOVAL
(1) Remove transaxle assembly. (Refer to 21 -
TRANSMISSION/TRANSAXLE/MANUAL -
REMOVAL)
(2) Remove modular clutch assembly from input
shaft (2.4L Gas models only).
(3) Grasp clutch release lever and bearing (Fig. 6)
with both hands and pull outward using moderate
pressure to release lever from pivot ball.
(4) Separate release bearing from lever.
NOTE: Remove release lever pivot ball(s) ONLY if
replacement is necessary.
Disconnect Tool, 6638A
Remover/Installer, 6891
6 - 6 CLUTCHRS
CLUTCH (Continued)
ProCarManuals.com