2005 CHRYSLER CARAVAN light

BRAKE NOISE
CONDITION POSSIBLE CAUSES CORRECTION
CLICK OR SQUAWK ON
PEDAL APPLICATION1. 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
CLUNK1. Broken or missing anti-rattle
spring clips on shoes.1. Replace brake shoes.
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.
DRUM BRAKE CHIRP 1. Lack of lubricant on brake shoe
support plate where shoes ride.1. Lubricate shoe contact areas on brake
shoe support plates.
DRUM BRAKE CLUNK 1. Drum(s) have threaded machined
braking surface.1. Replace brake drums as necessary.
DRUM BRAKE HOWL OR
MOAN1. Lack of lubricant on brake shoe
support plate where shoes ride and
at the anchor.1. Lubricate shoe contact areas on brake
shoe support plates and at the anchor.
2. Rear brake shoes. 2. Replace rear brake shoes.
DRUM BRAKE SCRAPING
OR WHIRRING1. ABS wheel speed sensor or tone
wheel.1. Inspect, correct or replace faulty
component(s).
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 and
drums. Reface or replace as necessary.
RSBRAKES - BASE5-5
BRAKES - BASE (Continued)

(3) Install the park brake actuator strut (Fig. 30)
on the leading brake shoe. Then install the park
brake actuator lever on the strut (Fig. 30).
(4) Install the automatic adjuster screw on the
leading brake shoe. Then install the trailing brake
shoe on the park brake actuating lever and park
brake actuating strut (Fig. 26). Position trailing
brake shoe on brake support plate.
(5) Install the brake shoe hold down pin and
spring on the trailing brake shoe (Fig. 25).
(6) Install the brake shoe to brake shoe upper
return spring (Fig. 24).
CAUTION: When installing the tension clip on the
automatic adjuster, it must be located on only the
threaded area of the adjuster assembly (Fig. 23). If it
is located on a non-threaded area of the adjuster, the
function of the automatic adjuster will be affected.
(7)Install the tension clip (Fig. 23) attaching the
upper return spring to the automatic adjuster assembly.
(8)Install the brake shoe to brake shoe lower return
springs on the brake shoes (Fig. 21) and (Fig. 22).
(9) Install automatic adjustment lever on the lead-
ing brake shoe of the rear brake assembly (Fig. 20).
(10) Install the actuating spring on the automatic
adjustment lever and leading brake shoe assembly
(Fig. 19).
(11) Verify that the automatic adjuster lever has
positive contact with the star wheel on the automatic
adjuster assembly.
(12) When all components of both rear brake
assemblies are correctly and fully installed, remove
the locking pliers from the front park brake cable.(13) Adjust brake shoes assemblies so as not to
interfere with brake drum installation.
(14) Install the rear brake drums on the hubs.
(15) Adjust rear brake shoes.
(16) Install the wheel and tire assembly.
(17) Tighten the wheel mounting stud nuts in
proper sequence until all nuts are torqued to half
specification. Then repeat the tightening sequence to
the full specified torque of 135 N´m (100 ft. lbs.).
(18) Lower the vehicle.
(19) Push the parking brake lever (pedal) to the
floor once and release pedal. This will automatically
remove the slack from and correctly adjust the park-
ing brake cables.
(20) Road test vehicle. The automatic adjuster will
continue the brake adjustment during the road test
of the vehicle.
ADJUSTMENTS
ADJUSTMENT - REAR DRUM BRAKE SHOES
NOTE: Normally, self-adjusting drum brakes do not
require manual brake shoe adjustment. Although, in
the event of a brake shoe replacement, it is advis-
able to make the initial adjustment manually to
speed up the adjusting time.
NOTE: Before raising the vehicle, verify the parking
brake lever is fully released.
(1) Raise the vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
(2) Remove rubber plug from rear brake adjusting
hole in the rear brake support plate.
(3) Insert a thin screwdriver through the adjusting
hole in the support plate and against the star wheel
of the adjusting screw. Move handle of the tool down-
ward, rotating the star wheel until a slight drag is
felt when tire and wheel assembly is rotated.
(4) Insert a second thin screwdriver or piece of
welding rod into brake adjusting hole and push the
adjusting lever out of engagement with the star
wheel.Care should be taken so as not to bend
adjusting lever or distort lever spring.
(5) While holding the adjusting lever out of
engagement, back off the star wheel just enough to
ensure a free wheel with no brake shoe drag.
(6) Repeat the above adjustment at the other rear
wheel.
(7) Install the adjusting hole rubber plugs back in
the rear brake support plates.
(8) Lower the vehicle.
Fig. 30 Park Brake Components Assembled On
Leading Brake Shoe
1 - PARK BRAKE CABLE
2 - LEADING BRAKE SHOE
3 - PARK BRAKE ACTUATING STRUT
4 - PARK BRAKE ACTUATING LEVER
5 - BRAKE SUPPORT PLATE
RSBRAKES - BASE5-23
BRAKE PADS/SHOES - REAR DRUM (Continued)

master cylinder reservoir from completely draining
out.
(3) Disconnect the brake fluid flex hose from the
caliper assembly and remove it from the vehicle.
CAUTION: Do not use excessive force when clamp-
ing caliper in vise. Excessive vise pressure will
cause bore distortion.
(4) Mount the caliper in a vise equipped with pro-
tective jaws.
(5) Remove the piston dust boot from the caliper
and discard.
NOTE: Do not use a screw driver or other metal tool
for seal removal. Using such tools can scratch the
bore or leave burrs on the seal groove edges.
(6) Using a soft tool such as a plastic trim stick,
work the piston seal out of its groove in caliper pis-
ton bore (Fig. 32). Discard the old seal.
(7) Clean the piston bore and drilled passage ways
using alcohol or a suitable solvent. Wipe it dry using
only a lint-free cloth.
(8) Inspect the piston bore for scoring or pitting.
Bores that show light scratches or corrosion can usu-
ally be cleared of the light scratches or corrosion
using crocus cloth.CLEANING - CALIPER
WARNING: DUST AND DIRT ACCUMULATING ON
BRAKE PARTS DURING NORMAL USE MAY CON-
TAIN ASBESTOS FIBERS FROM PRODUCTION OR
AFTERMARKET BRAKE LININGS. BREATHING
EXCESSIVE CONCENTRATIONS OF ASBESTOS
FIBERS CAN CAUSE SERIOUS BODILY HARM.
EXERCISE CARE WHEN SERVICING BRAKE
PARTS. DO NOT SAND OR GRIND BRAKE LINING
UNLESS EQUIPMENT USED IS DESIGNED TO CON-
TAIN THE DUST RESIDUE. DO NOT CLEAN BRAKE
PARTS WITH COMPRESSED AIR OR BY DRY
BRUSHING. CLEANING SHOULD BE DONE BY
DAMPENING THE BRAKE COMPONENTS WITH A
FINE MIST OF WATER, THEN WIPING THE BRAKE
COMPONENTS CLEAN WITH A DAMPENED CLOTH.
DISPOSE OF CLOTH AND ALL RESIDUE CONTAIN-
ING ASBESTOS FIBERS IN AN IMPERMEABLE
CONTAINER WITH THE APPROPRIATE LABEL. FOL-
LOW PRACTICES PRESCRIBED BY THE OCCUPA-
TIONAL SAFETY AND HEALTH ADMINISTRATION
(OSHA) AND THE ENVIRONMENTAL PROTECTION
AGENCY (EPA) FOR THE HANDLING, PROCESSING,
AND DISPOSING OF DUST OR DEBRIS THAT MAY
CONTAIN ASBESTOS FIBERS.
To clean or flush the internal passages of the brake
caliper, use fresh brake fluid or MopartNon-Chlori-
nated Brake Parts Cleaner. Never use gasoline, ker-
osene, alcohol, oil, transmission fluid or any fluid
containing mineral oil to clean the caliper. These flu-
ids will damage rubber cups and seals.
INSPECTION - CALIPER
Inspect the disc brake caliper for the following:
²Brake fluid leaks in and around boot area and
inboard lining
²Ruptures, brittleness or damage to the piston
dust boot
²Damaged, dry or brittle guide pin dust boots
If caliper fails inspection, disassemble and recondi-
tion caliper, replacing the seals and dust boots.
ASSEMBLY
ASSEMBLY - CALIPER GUIDE PIN BUSHINGS
(CONTINENTAL TEVES BRAKES)
(1) Fold the guide pin bushing in half lengthwise.
NOTE: To avoid damage to the bushing, do not use
a sharp object to install the guide pin bushing.
(2) Insert the folded bushing into the caliper
mounting boss using your fingers from the rear of
the caliper.
Fig. 32 Removing Piston Seal
1 - PLASTIC TRIM STICK
2 - CALIPER
3 - PISTON SEAL GROOVE
4 - PISTON SEAL
RSBRAKES - BASE5-25
DISC BRAKE CALIPER - FRONT (Continued)

(3) Disconnect the brake fluid flex hose from the
caliper assembly and remove it from the vehicle.
CAUTION: Do not use excessive force when clamp-
ing caliper in vise. Excessive vise pressure will
cause bore distortion.
(4) Mount the caliper in a vise equipped with pro-
tective jaws.
(5) Remove the piston dust boot from the caliper
and discard.
NOTE: Do not use a screw driver or other metal tool
for seal removal. Using such tools can scratch the
bore or leave burrs on the seal groove edges.
(6) Using a soft tool such as a plastic trim stick,
work the piston seal out of its groove in caliper pis-
ton bore (Fig. 38). Discard the old seal.
(7) Clean the piston bore and drilled passage ways
using alcohol or a suitable solvent. Wipe it dry using
only a lint-free cloth.
(8) Inspect the piston bore for scoring or pitting.
Bores that show light scratches or corrosion can usu-
ally be cleared of the light scratches or corrosion
using crocus cloth.CLEANING - CALIPER
WARNING: DUST AND DIRT ACCUMULATING ON
BRAKE PARTS DURING NORMAL USE MAY CON-
TAIN ASBESTOS FIBERS FROM PRODUCTION OR
AFTERMARKET BRAKE LININGS. BREATHING
EXCESSIVE CONCENTRATIONS OF ASBESTOS
FIBERS CAN CAUSE SERIOUS BODILY HARM.
EXERCISE CARE WHEN SERVICING BRAKE
PARTS. DO NOT SAND OR GRIND BRAKE LINING
UNLESS EQUIPMENT USED IS DESIGNED TO CON-
TAIN THE DUST RESIDUE. DO NOT CLEAN BRAKE
PARTS WITH COMPRESSED AIR OR BY DRY
BRUSHING. CLEANING SHOULD BE DONE BY
DAMPENING THE BRAKE COMPONENTS WITH A
FINE MIST OF WATER, THEN WIPING THE BRAKE
COMPONENTS CLEAN WITH A DAMPENED CLOTH.
DISPOSE OF CLOTH AND ALL RESIDUE CONTAIN-
ING ASBESTOS FIBERS IN AN IMPERMEABLE
CONTAINER WITH THE APPROPRIATE LABEL. FOL-
LOW PRACTICES PRESCRIBED BY THE OCCUPA-
TIONAL SAFETY AND HEALTH ADMINISTRATION
(OSHA) AND THE ENVIRONMENTAL PROTECTION
AGENCY (EPA) FOR THE HANDLING, PROCESSING,
AND DISPOSING OF DUST OR DEBRIS THAT MAY
CONTAIN ASBESTOS FIBERS.
To clean or flush the internal passages of the brake
caliper, use fresh brake fluid or MopartNon-Chlori-
nated Brake Parts Cleaner. Never use gasoline, ker-
osene, alcohol, oil, transmission fluid or any fluid
containing mineral oil to clean the caliper. These flu-
ids will damage rubber cups and seals.
INSPECTION - CALIPER
Inspect the disc brake caliper for the following:
²Brake fluid leaks in and around boot area and
inboard lining
²Ruptures, brittleness or damage to the piston
dust boot
²Damaged, dry or brittle guide pin dust boots
If caliper fails inspection, disassemble and recondi-
tion caliper, replacing the seals and dust boots.
Fig. 38 Removing Piston Seal
1 - PLASTIC TRIM STICK
2 - CALIPER
3 - PISTON SEAL GROOVE
4 - PISTON SEAL
RSBRAKES - BASE5-29
DISC BRAKE CALIPER - REAR (Continued)

CAUTION: When tightening the primary and sec-
ondary brake tube nuts at master cylinder, be sure
brake tubes do not contact any other components
within the vehicle and that there is slack in the flex-
ible sections of the tubes. This is required due to
the movement between the ABS ICU and the master
cylinder while the vehicle is in motion.
(4) Connect primary and secondary brake tubes to
master cylinder primary and secondary ports (Fig.
50). Brake tubes must be held securely when tight-
ened to control orientation of flex section. Tighten
tube nuts to a torque of 17 N´m (145 in. lbs.).
(5) Install wiring harness connector to brake fluid
level switch mounted in brake fluid reservoir (Fig.
46).
(6) Install battery, clamp and nut.
(7) Install battery shield.
(8) Connect positive battery terminal.
(9) Connect negative battery terminal.
(10) Fill master cylinder with clean, fresh Mopart
Brake Fluid or equivalent.
(11) Road test vehicle to ensure proper operation of
brakes.
PEDALS - ADJUSTABLE
REMOVAL
NOTE: Before proceeding, review all Steering Col-
umn and Airbag Warnings and Cautions. (Refer to
19 - STEERING/COLUMN - WARNING)(Refer to 8 -
ELECTRICAL/RESTRAINTS - WARNING)
(1) Move driver's seat to full rearward position.
(2) Disconnect negative battery cable from battery
post and isolate.
(3) Remove throttle cable from throttle body lever.
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
THROTTLE CONTROL CABLE - REMOVAL)
(4) Remove screws securing lower steering column
cover/knee blocker, then remove it (Fig. 53).
(5) Disconnect parking brake release link at
release handle.
(6) Compress tabs on sides of data link diagnostic
connector and remove it from knee blocker reinforce-
ment plate.
(7) Remove screws securing knee blocker reinforce-
ment plate in place, then remove reinforcement plate
(Fig. 53).
(8) Remove hood release from lower left reinforce-
ment.
(9) Remove screws securing instrument panel
lower left reinforcement in place, then remove rein-
forcement (Fig. 54).(10) Remove brake lamp switch.Discard original
switch; it must not be reused.(Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/BRAKE
LAMP SWITCH - REMOVAL)
(11) Remove upper and lower steering column
shrouds. (Refer to 19 - STEERING/COLUMN/
LOWER SHROUD - REMOVAL)
Fig. 53 Lower Steering Column Cover And
Reinforcement
1 - INSTRUMENT PANEL
2 - REINFORCEMENT PLATE
3 - LOWER STEERING COLUMN COVER/KNEE BLOCKER
Fig. 54 Instrument Panel Lower Left Reinforcement
1 - INSTRUMENT PANEL LOWER REINFORCEMENT
2 - STEERING WHEEL
3 - LOWER LEFT REINFORCEMENT
5 - 40 BRAKES - BASERS
MASTER CYLINDER (Continued)

INSTALLATION
(1) Install adjustable pedals assembly under
instrument panel.
(2) Attach throttle cable to accelerator pedal using
cable retainer.
(3) Install two upper mounting bolts attaching
pedals assembly to steering column support bracket
on dash panel.Do not fully tighten at this time.
(4) Install four nuts attaching pedals assembly and
power brake booster to dash panel (Fig. 61).
(5) Tighten four booster mounting nuts and two
upper mounting bolts to 28 N´m (21 ft. lbs.) torque.
(6) Route pedal adjuster cable up and over right
side of pedals assembly and steering column bracket,
then down through hole in steering column bracket
as shown (Fig. 60). Attach end of cable to gear box.
(7) Place adjuster cable through loop on right side
of steering column bracket as shown (Fig. 60).
(8) Install booster input rod onto brake pedal pin
and install a NEW retaining clip.
(9) Connect wiring connector connecting vehicle
wiring harness to pedal wiring harness (Fig. 58).
(10) Connect routing clips retaining vehicle wiring
harness to pedal wiring harness (Fig. 58).
(11) Install brake lamp switch bracket on pedals
assembly. Tighten mounting nuts to 6 N´m (50 in.
lbs.) torque.
(12) Install dash seal silencer shell over steering
column intermediate shaft and fasten in place (Fig.
57).
(13) Install steering column onto lower mounting
studs with nuts started, then install column onto
upper mounting studs and install two upper mount-
ing nuts. Tighten upper, then lower mounting nuts to
12 N´m (105 in. lbs.) torque.
(14) Install column shaft coupling onto intermedi-
ate shaft and install pinch bolt. Make sure rounded
side of intermediate shaft is matched to the curva-
ture of the coupling. Tighten pinch bolt to 28 N´m
(250 in. lbs.) torque.
(15) Remove retainer holding steering wheel in
place on steering column.
(16) Attach shift cable to bracket on column.
(17) Connect shift cable end to shift lever mecha-
nism pin (Fig. 55).
(18) If equipped, connect PRNDL cable to end of
shift lever mechanism pin and column bracket (Fig.
55).(19) Connect column wiring harness connectors (as
equipped) to SKIM, BTSI solenoid, ignition switch,
multi-function switch, and clockspring.
(20) Install lower and upper steering column
shrouds. (Refer to 19 - STEERING/COLUMN/
LOWER SHROUD - INSTALLATION)
CAUTION: Do not reuse the original brake lamp
switch. The switch can only be adjusted once. That
is during initial installation of the switch. If the
switch is not adjusted properly or has been
removed for some service, a new switch must be
installed and adjusted.
(21) Install and adjust NEW brake lamp switch.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/BRAKE LAMP SWITCH - INSTALLA-
TION)
(22) Install instrument panel lower left reinforce-
ment (Fig. 54).
(23) Attach hood release to lower left reinforce-
ment.
(24) Install knee blocker reinforcement plate (Fig.
53).
(25) Connect parking brake release link to release
handle.
(26) Install data link diagnostic connector to
mounting hole in reinforcement plate.
(27) Install lower steering column cover/knee
blocker (Fig. 53).
(28) Install throttle cable onto throttle body lever.
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
THROTTLE CONTROL CABLE - INSTALLATION)
NOTE: When reconnecting the battery on a vehicle
that has had the airbag module removed, the fol-
lowing procedure should be used.
(29) Reconnect ground cable to negative post of
battery following special Diagnosis And Testing pro-
cedure. (Refer to 8 - ELECTRICAL/RESTRAINTS -
DIAGNOSIS AND TESTING)
(30) Test operation of adjustable pedals and all
functions that are steering column operated. If appli-
cable, reset radio and clock.
(31) Road test the vehicle to ensure proper opera-
tion of steering and brake systems.
RSBRAKES - BASE5-43
PEDALS - ADJUSTABLE (Continued)

(7) Connect the brake pedal link to the torque
shaft. Install a NEW retaining clip at the torque
shaft end of the brake pedal-to-torque shaft link.
(8) Install the HVAC housing. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION/HVAC
HOUSING - INSTALLATION)
(9) Install the instrument panel. (Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL ASSEMBLY - INSTALLATION)
CAUTION: Do not reuse the original brake lamp
switch. The switch can only be adjusted once. That
is during initial installation of the switch. If the
switch is not adjusted properly or has been
removed for some service, a new switch must be
installed and adjusted.
(10) Remove and replace the brake lamp switch
with a NEW switch. (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - EXTERIOR/BRAKE LAMP
SWITCH - REMOVAL), (Refer to 8 - ELECTRICAL/
LAMPS/LIGHTING - EXTERIOR/BRAKE LAMP
SWITCH - INSTALLATION)
(11) Road test vehicle to ensure proper operation of
the brakes.
POWER BRAKE BOOSTER
DESCRIPTION
The power brake booster mounts on the engine
compartment side of the dash panel. It is connected
to the brake pedal by the input (push) rod (Fig. 64).
The master cylinder is bolted to the front of the
booster. A vacuum line connects the power brake
booster to the intake manifold.
All Left-Hand-Drive (LHD) vehicles use a 270 mm
single diaphragm vacuum power brake booster. All
Right-Hand-Drive (RHD) vehicles use a 225/200 mm
tandem diaphragm vacuum power brake booster.
Vehicles equipped with Disc/Disc brakes use a dif-
ferent power brake booster than vehicles equipped
with Disc/Drum brakes. Differences between the two
are internal. Service is the same for all boosters.
The power brake booster can be identified by the
tag attached to the body of the booster (Fig. 65). 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.
Fig. 64 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. 65 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 - BASE5-45
PEDAL TORQUE SHAFT - RHD (Continued)

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. 64).
As the brake pedal is depressed, the power brake
booster's input rod moves forward (Fig. 64). 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.
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 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.
(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.
5 - 46 BRAKES - BASERS
POWER BRAKE BOOSTER (Continued)