Downloaded from www.Manualslib.com manuals search engine 4A-1 Brake Control System and Diagnosis:
Brakes
Brake Control System and Diagnosis
Precautions
Precautions on BrakeS6RW0D4100001
Air Bag Warning
Refer to“Air Bag Warning in Section 00”.
Brakes Diagnosis Note
Refer to “Brakes Diagnosis Note”.
General Description
Brakes ConstructionS6RW0D4101001
When the foot brake pedal is depressed, hydraulic pressure is developed in the master cylinder to actuate pistons (two
in front and four in rear).
The master cylinder is a tandem master cylinder. Brake pipes are connected to the master cylinder and they make two
independent circuits. One connects front right & rear left brakes and the other connects front left & rear right brakes.
In this brake system, the disc brake is used for the front wheel brake and drum brake (leading / trailing shoes) for the
rear brake.
The parking brake system is mechanical. It applies brake force to only rear wheels by means of the cable and
mechanical linkage system. The same brake shoes of rear drum brake are used for both parking and foot brakes.
NOTE
• The figures show LH steering vehicle.
• The difference between RH steering vehicle and LH steering vehicle is the location of the brake
master cylinder, the brake booster and ABS hydraulic unit / control module assembly.
A
421
37
7
658
I7RW01410001-01
1. Brake booster 4. Primary side 7. Parking brake cable
2. Master cylinder 5. ABS hydraulic unit / control module assembly 8. 4-way joint
3. Secondary side 6. Parking brake lever A: Forward
Downloaded from www.Manualslib.com manuals search engine Brake Control System and Diagnosis: 4A-4
Rear Brake Hose / Pipe ConstructionS6RW0D4101003
Diagnostic Information and Procedures
Brakes Diagnosis NoteS6RW0D4104001
Road Testing Brakes
Brakes should be tested on dry, clean, smooth and
reasonably level roadway which is not crowned. Road
test brakes by making brake applications with both light
and heavy pedal forces at various speeds to determine if
the vehicle stops evenly and effectively. Also drive
vehicle to see if it leads to one side or the other without
brake application. If it does, check the tire pressure, front
wheel alignment and front suspension attachments for
looseness. See diagnosis table for other causes.
Brake Fluid Leaks
Check the master cylinder fluid levels. While a slight
drop in reservoir level does result from normal lining
wear, an abnormally low level indicates a leak in the
system. In such a case, check the entire brake system
for leakage. If even a slight evidence of leakage is noted,
the cause should be corrected or defective parts should
be replaced.Substandard or Contaminated Brake Fluid
Improper brake fluid, mineral oil or water in the fluid may
cause the brake fluid to boil or the rubber components
(piston cups and brake hoses) in the hydraulic system to
deteriorate.
If the above fluid is included in the system, replace the
master cylinder assembly and other rubber components
(hoses). The master cylinder assembly is disassemble
parts to maintain the performance.
The system must be flushed if there is any doubt as to
the grade of fluid in the system or if fluid has been used
which contained parts that have been subjected to
contaminated fluid.
I6RW0D410001-01
1. To left rear brake hose 5. Left rear brake hose to left brake
2. To right rear brake hose 6. Right rear brake hose to right brake
3. Left rear brake hose : 16 N⋅m (1.6 kgf-m, 12.0 lb-ft)
4. Right rear brake hose
Downloaded from www.Manualslib.com manuals search engine 4A-5 Brake Control System and Diagnosis:
Brakes Symptom DiagnosisS6RW0D4104002
Condition Possible cause Correction / Reference Item
Not enough braking forceBrake oil leakage from brake linesLocate leaking point and repair.
Brake disc or pad stained with oilClean or replace.
Overheated brakesDetermine cause and repair.
Poor contact of shoes on brake drumRepair for proper contact.
Brake shoe stained with oil or wet with
waterReplace.
Badly worn brake padReplace.
Defective wheel cylindersRepair or replace.
Malfunctioning caliper assemblyRepair or replace.
Malfunctioning brake boosterCheck system and replace as necessary.
Malfunctioning brake master cylinderCheck system and replace as necessary.
Air in systemBleed system.
Malfunctioning ABSCheck system and replace as necessary.
Brake pull (Brakes not
working in unison)Pad, disc, shoe and/or drum are wet
with water or stained with oil in some
brakesClean or replace.
Drum-to-shoe clearance out of
adjustment in some brakes
(Malfunctioning auto adjusting
mechanism) Check for inoperative auto adjusting
mechanism.
Disc and/or drum are out of round in
some brakesReplace.
Tires are inflated unequallyInflate equally.
Malfunction in wheel cylinders (rear
drum brake model)Repair or replace.
Disturbed front wheel alignmentAdjust as prescribed.
Unmatched tires on same axleTires with approximately the same amount of
tread should be used on the same axle.
Restricted brake pipes or hosesCheck for soft hoses and damaged lines.
Replace with new hoses and new double-
walled steel brake tubing.
Malfunctioning caliper assemblyCheck for stuck or sluggish pistons and proper
lubrication of caliper slide pin.
Caliper should slide.
Loose suspension partsCheck all suspension mountings.
Loose calipersCheck and torque bolts to specifications.
Noise (high pitched
squeak without brake
applied)Contact wear indicator to brake discReplace brake pad.
Worn rear brake shoeReplace brake shoe.
Excessive pedal travel
(Pedal stroke too large)Partial brake system failureCheck brake systems and repair as necessary.
Brake fluid leakingRepair the leaking point, and bleed air.
Air in system (soft / spongy pedal)Bleed system.
Rear brake system not adjusted
(malfunctioning auto adjusting
mechanism)Repair auto adjusting mechanism.
Adjust rear brakes.
Bent brake shoesReplace brake shoes.
Brake locked Malfunctioning ABSCheck system referring to “ABS Check in
Section 4E”.
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Dragging brakes (Without
a very light drag is
present in all brakes
immediately after pedal is
released)Master cylinder pistons not returning
correctlyReplace master cylinder.
Restricted brake pipes or hosesCheck for soft hoses or damaged pipes and
replace with new hoses and/or new brake
piping.
Incorrect parking brake adjustment on
rear brakesCheck and adjust to correct specifications.
Weakened or broken return springs in
the drum brakeReplace.
Sluggish parking brake cables or linkageRepair or replace.
Wheel cylinder or caliper piston stickingRepair as necessary.
Badly worn piston seal in caliperReplace piston seal.
Improper brake pedal free heightCheck brake pedal free height.
Pedal pulsation (Pedal
pulsates when depressed
for braking)Damaged wheel bearingsReplace wheel bearings.
Distorted steering knuckle or rear wheel
spindle or rear axle shaftReplace knuckle or rear wheel spindle or rear
axle shaft.
Excessive disc lateral runoutCheck per instructions. If not within
specifications, replace or machine disc.
Rear drums out of roundCheck runout.
Repair or replace drum as necessary.
Braking noiseGlazed brake pad and/or brake shoeRepair or replace brake pad and/or brake
shoe.
Worn or distorted brake shoeReplace brake shoe.
Loose front wheel bearingsReplace wheel hub.
Distorted backing plates or loose
mounting boltsReplace or retighten securing bolts.
Contact wear indicator to brake discReplace brake pads.
Brake warning light lights
after engine startParking brake appliedRelease parking brake and check that brake
warning light turns off.
Insufficient amount of brake fluidInvestigate leaky point, correct it and add
brake fluid.
Brake fluid leakingInvestigate leaky point, correct it and add
brake fluid.
Brake warning light circuit faultyRepair circuit.
Malfunctioning EBD systemCheck system referring to “EBD Warning Light
(Brake Warning Light) Comes ON Steady in
Section 4E”.
Brake warning light turns
on when brake is appliedBrake fluid leakingInvestigate leaky point, correct it and add
brake fluid.
Insufficient amount of brake fluidInvestigate leaky point, correct it and add
brake fluid.
Brake warning light fails
to turn on even when
parking brake is appliedBrake warning light circuit faultyReplace bulb or repair circuit.
ABS warning light turns
on after engine startMalfunctioning ABSCheck system referring to “ABS Check in
Section 4E”.
ABS warning light turns
on when brake is appliedMalfunctioning ABSCheck system referring to “ABS Check in
Section 4E”.
ABS warning light after
ignition switch has turned
ON Bulb burnt outReplace bulb.
Malfunctioning ABSCheck system referring to “ABS Check in
Section 4E”.
ABS warning light flashesNew ABS hydraulic unit / control module
assembly installed.Perform “ABS Hydraulic Unit Operation Check
in Section 4E”. Condition Possible cause Correction / Reference Item
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Brake Fluid Level InspectionS6RW0D4106004
CAUTION!
Do not use shock absorber fluid or any other
fluid which contains mineral oil. Do not use a
container which has been used for mineral oil
or a container which is wet from water.
Mineral oil will cause swelling and distortion
of rubber parts in hydraulic brake system and
water mixed into brake fluid will lower fluid
boiling point. Keep all fluid containers
capped to prevent contamination.
NOTE
Be sure to use particular brake fluid either as
indicated on reservoir cap of that vehicle or
recommended in owner’s manual which
comes along with that vehicle. Use of any
other fluid is strictly prohibited.
Fluid level should be between MIN and MAX
lines marked on reservoir.
When brake warning light lights sometimes
during driving, replenish fluid to MAX level.
When fluid decreases quickly, inspect brake
system for leakage. Correct leaky points and
then refill to specified level.
1) Check master cylinder, reservoir and reservoir hose
(if equipped) for crack, damage and brake fluid
leakage. If any faulty condition exists, correct or
replace.
2) Check that brake fluid level is between MAX (1) and
MIN marks (2) on reservoir.
Brake Light Switch AdjustmentS6RW0D4106005
Adjustment should be made as follows. Pull up brake
pedal toward you and while holding it there, adjust
switch position so that clearance between end of thread
and brake pedal is as specified. Then lock it by turning
clockwise.
Clearance between brake pedal and brake light
switch
“a”: 0.5 – 1.5 mm (0.02 – 0.05 in.)
Air Bleeding of Brake SystemS6RW0D4106006
CAUTION!
Brake fluid is extremely damaging to paint. If
fluid should accidentally touch painted
surface, immediately wipe fluid from paint
and clean painted surface.
Bleeding operation is necessary to remove air whenever
it entered hydraulic brake system.
Hydraulic lines of brake system are based on the
diagonal split system. When a brake pipe or hose was
disconnected at the wheel, bleeding operation must be
performed at both ends of the line of the removed pipe or
hose. When any joint part of the master cylinder of other
joint part between the master cylinder and each brake
(wheel) was removed, the hydraulic brake system must
be bled at all 4 wheel brakes.
NOTE
Perform bleeding operation starting with rear
brake caliper or wheel cylinder farthest from
master cylinder and then at front caliper of
the same brake line. Do the same on the
other brake line.
1
2
I7RW01410004-01
1. Right front brake caliper 3. Right rear wheel cylinder
2. Left front brake caliper 4. Left rear wheel cylinder
I5RW0A410005-01
I7RW01410005-01
Downloaded from www.Manualslib.com manuals search engine 4B-1 Front Brakes:
Brakes
Front Brakes
Repair Instructions
Front Disc Brake ComponentsS6RW0D4206001
I7RW01420001-05
1. Caliper 9. Disk brake piston
: Apply rubber grease included in piston
seal set or brake fluid to contact surface of
cylinder.17. Brake flexible hose
: Be sure to direct mark (18) to
inside of vehicle “I” as shown in
figure.
2. Caliper pin bolt 10. Pad spring
: Apply grease included in brake pad spare
parts to inside.: 26 N⋅m (2.6 kgf-m, 19.0 lb-ft)
3. Boot 11. Brake disc : 23 N⋅m (2.3 kgf-m, 17.0 lb-ft)
4. Slide pin No.1
: Apply rubber grease included in slide pin / boot
set.12. Brake caliper carrier : 9 N⋅m (0.9 kgf-m, 6.5 lb-ft)
5. Brake pad 13. Caliper carrier bolt : 85 N⋅m (8.5kgf-m, 61.5 lb-ft)
6. Shim 14. Bleeder plug : Do not reuse.
7. Cylinder boot
: Apply small amount of rubber grease included
in piston seal set or brake fluid.15. Flexible hose joint bolt
8. Piston seal
: Apply small amount of rubber grease included
in piston seal set or brake fluid.16. Hose washer
Downloaded from www.Manualslib.com manuals search engine Front Brakes: 4B-2
Front Disc Brake Pad On-Vehicle InspectionS6RW0D4206002
Inspect pad linings (1) periodically according to
maintenance schedule whenever wheels are removed
(for tire rotation or other reason). Take a look through
each end and inspection hole of caliper and check lining
thickness of outside and inside pads.
If lining is worn and its thickness (“a” in figure) is less
than limit, all pads must be replaced at the same time.
Front brake pad thickness “a” (lining thickness)
Standard: 10 mm (0.39 in.)
Limit: 2 mm (0.08 in.)
Front Disc Brake Pad Removal and InstallationS6RW0D4206003
NOTE
When replacing brake pad, replace it on the
right and left.
Removal
1) Hoist vehicle and remove front wheel.
2) Remove caliper pin bolts (1).
3) Remove caliper (1) from caliper carrier (2).
NOTE
Hang removed caliper (1) with a wire hook (4)
or the like so as to prevent brake hose from
bending and twisting excessively or being
pulled.
Don’t operate brake pedal with brake pads
removed.
4) Remove brake pads (3).
5) Remove brake pad spring (1) as show in figure.
Installation
1) Apply small amount of pad grease “a” (included in
spare parts) to pad spring and set brake pad spring
as shown in figure.
2) Set brake pad springs (1), and install brake pads (2)
and shim (4).
NOTE
Install the brake pad with wear indicator (3) to
the vehicle center side of front right brake
pad.
I7RW01420009-01
1
I7RW01420003-01
42
3
1
I7RW01420010-01
1
I7RW01420014-01
"a"
I7RW01420011-01
I7RW01420012-01
Downloaded from www.Manualslib.com manuals search engine 4B-3 Front Brakes:
3) Install caliper and tighten caliper pin bolts to
specified torque.
Tightening torque
Caliper pin bolt (a): 26 N·m (2.6 kgf-m, 19.0 lb-ft)
4) Install front wheel referring to “Wheel (with Tire)
Removal and Installation in Section 2D”.
5) Check brake effectiveness.
Front Disc Brake Pad InspectionS6RW0D4206004
Check pad lining for wear. When the wear exceeds limit,
replace with new one.
CAUTION!
Never polish pad lining with sandpaper. If
lining is polished with sandpaper, hard
particles of sandpaper will be deposited in
lining and may damage disc. When pad lining
requires correction, replace it with a new one.
Front disc brake pad thickness (lining thickness)
Standard: 10 mm (0.39 in.)
Limit: 10 mm (0.39 in.)
NOTE
When pads are removed, visually inspect
caliper for brake fluid leak. Correct leaky
point, if any.
Front Disc Brake Caliper Removal and
Installation
S6RW0D4206005
Removal
1) Hoist vehicle and remove front wheel.
2) Remove brake flexible hose joint bolt (1) from caliper
(2). As this will allow fluid to flow out of hose (3),
have a container ready beforehand.
3) Remove caliper pin bolts (1).
4) Remove caliper from caliper carrier.
Installation
1) Install caliper to caliper carrier.
2) Torque caliper pin bolts to specification.
NOTE
Make sure that boots are fit into groove
securely.
Tightening torque
Caliper pin bolt (a): 26 N·m (2.6 kgf-m, 19.0 lb-ft)
(a)
I7RW01420005-02
I2RH01420005-01
I7RW01420006-01
1
I7RW01420003-01
(a)
I7RW01420005-02