YH4
GRAND
VITARA
[FOR VEHICLE WITHOUT ABS]
[FOR VEHICLE WITH ABS]
1. Master cylinder
2-1. 4-way joint
2-2. 2-way joint
3. LSPV (Load Sensing Proportioning Valve)
4. Rear axle housing
5. ABS actuator (H.U.)
F.R.:Front side
5-2 BRAKES
GENERAL DESCRIPTION
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 brakes (right and left) and the other connects rear brakes (right and
left).
The load sensing proportioning valve (LSPV) is included in these circuits between the master cylinder and the rear
brake for the vehicle without ABS.
In this brake system, the disc brake type is used for the front wheel brake and a drum brake type (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 me-
chanical linkage system. The same brake shoes are used for both parking and foot brakes.
YH4
GRAND
VITARA
5-4 BRAKES
DIAGNOSIS TABLE
ConditionPossible CauseCorrection
Not enough brak-
ing forceBrake oil leakage from brake lines.
Brake disc or pads stained with oil.
Overheated brakes.
Poor contact of shoes on brake drum.
Brake shoes linings stained with oil or wet
with water.
Badly worn brake shoe linings.
Defective wheel cylinders.
Malfunctioning caliper assembly.
Air in system.
Maladjusted sensor spring length of LSPV.
Broken sensor spring of LSPV.
Defective collar of LSPV.
Malfunctioning ABS (Antilock brake system),
if equipped.Locate leaking point and repair.
Clean or replace.
Determine cause and repair.
Repair for proper contact.
Replace.
Replace.
Repair or replace.
Repair or replace.
Bleed system.
Check or adjust.
Replace.
Replace.
Check system and replace as
necessary.
Brake pull
(Brakes not work-
ing in unison)Pad or shoe linings are wet with water or
stained with oil in some brakes.
Drum-to-shoe clearance out of adjustment in
some brakes.
(Malfunctioning auto adjusting mechanism)
Drum is out of round in some brakes.
Wheel tires are inflated unequally.
Malfunctioning wheel cylinders.
Disturbed front end alignment.
Unmatched tires on same axle.
Restricted brake pipes or hoses.
Malfunctioning caliper assembly.
Loose suspension parts.
Loose calipers.Replace.
Check for inoperative auto adjusting
mechanism.
Replace.
Inflate equally.
Repair or replace.
Adjust as prescribed.
Tires with approximately the same
amount of tread should be used on the
same axle.
Check for soft hoses and damaged
lines.
Replace with new hoses and new
brake pipes.
Check for stuck or sluggish pistons
and proper lubrication of caliper slide
bush.
Caliper should slide.
Check all suspension mountings.
Check and torque bolts to specifica-
tions.
Noise (High pitched
squeak without
brake applied)Front lining worn out.Replace linings.
Rear brake locked
prematurelyMaladjusted sensor spring length of LSPV.
Malfunction LSPV assembly.Check or adjust.
Replace assembly.
Brake locked
(For vehicles
equipped with
ABS)Malfunctioning ABS, if equipped.Check system and replace as
necessary.
YH4
GRAND
VITARA
BRAKES 5-5
ConditionPossible CauseCorrection
Excessive pedal
travel (Pedal
stroke too large)Partial brake system failure.
Insufficient fluid in master cylinder
reservoirs.
Air in system. (pedal soft / spongy)
Rear brake system not adjusted.
(malfunctioning auto adjusting mechanism)
Bent brake shoes.
Worn rear brake shoes.Check brake systems and repair as
necessary.
Fill reservoirs with approved brake
fluid.
Check for leaks and air in brake
systems.
Check warning light. Bleed system if
required.
Bleed system.
Repair auto adjusting mechanism.
Adjust rear brakes.
Replace brake shoes.
Replace brake shoes.
Dragging brakes
(A very light drag
is present in all
disc brakes
immediately
after pedal is
released)Master cylinder pistons not returning
correctly.
Restricted brake pipes or hoses.
Incorrect parking brake adjustment on rear
brakes.
Weakened or broken return springs in the
brake.
Sluggish parking-brake cables or linkage.
Wheel cylinder or caliper piston sticking.
Malfunctioning ABS, if equipped with ABS.Replace master cylinder.
Check for soft hoses or damaged
pipes and replace with new hoses
and / or new brake pipes.
Check and adjust to correct specifi-
cations.
Replace.
Repair or replace.
Repair as necessary.
Check system and replace as
necessary.
Pedal pulsation
(Pedal pulsates
when depressed
for braking)Damaged or loose wheel bearings.
Distorted steering knuckle or rear axle
shafts.
Excessive disc lateral runout.
Parallelism not within specifications.
Rear drums out of round.Replace wheel hub component.
Replace knuckle or rear axle shaft.
Check per instructions. If not within
specifications, replace or machine
the disc.
Check per instructions. If not within
specifications, replace or machine
the disc.
Check runout.
Repair or replace drum as
necessary.
Braking noiseGlazed shoe linings, or foreign matters
stuck to linings.
Worn or distorted shoe linings.
Loose front wheel bearings.
Distorted backing plates or loose mounting
bolts.Repair or replace shoe lining.
Replace shoe lining (or pad).
Replace wheel hub component.
Replace or retighten securing bolts.
YH4
GRAND
VITARA
1. 4-way joint / 2-way joint
2. Master cylinder
3. LSPV
4. Right brake caliper
5. Left brake caliper
6. Right wheel cylinder
7. Left wheel cylinder
8. ABS actuator
: Air bleeding point [A]: Without ABS
[B]: With ABS
1. Plug cap2. Vinyl tube (See-through tube)
3. Container
[A]
[B]
BRAKES 5-7
CHECK AND ADJUSTMENT
BLEEDING BRAKES
CAUTION:
Brake fluid is extremely damaging to paint. If fluid should
accidentally touch painted surface, immediately wipe
fluid from paint and clean painted surface.
NOTE:
For vehicle equipped with ABS, make sure that ignition switch
turns off.
Be sure to bleed air of brake system according to following proce-
dure when its oil hydraulic circuit has been disconnected.
Hydraulic lines of brake system consists of two separate lines, one
for front wheel brakes and the other for rear wheel brakes.
Air bleeding is necessary at right and left front wheel brakes, left
rear wheel brake and LSPV (if equipped without ABS), i.e. 4 places
(3 places for vehicle with ABS) in all.
1) Fill master cylinder reservoir with brake fluid and keep at least
one-half full of fluid during bleeding operation.
2) Remove bleeder plug cap.
Attach a vinyl tube to bleeder plug of wheel cylinder, and insert
the other end into container.
3) Depress brake pedal several times, and then while holding it de-
pressed, loosen bleeder plug about one-third to one half turn.
YH4
GRAND
VITARA
1. Stop light switch
BRAKES 5-9
BRAKE PEDAL FREE HEIGHT CHECK
Remove foot rest and displace carpet and dash silencer(s) so as to
measure brake pedal free height between pedal face and asphalt
sheet installed on dash panel.
Brake pedal free height ªaº from asphalt sheet:
208 ± 218 mm (8.19 ± 8.58 in.)
If the measurement is not within the specification, check the posi-
tion of booster push rod clevis and / or stop light switch according
to the instruction shown in this section.
The free height varies depending on installation position of booster
push rod clevis and stop light switch.
BRAKE LIGHT SWITCH ADJUSTMENT
Adjustment should be made as follows when installing switch. Pull
up brake pedal toward you and while holding it there, adjust switch
position so that clearance between end of thread and brake pedal
return cushion (shown as ªbº in figure).
Then tighten lock nut to specified torque.
Clearance ªbº: 1.5 ± 2.0 mm (0.06 ± 0.08 in.)
Tightening Torque
(b): 7.5 N
.m (0.75 kg-m, 5.5 lb-ft)
EXCESSIVE PEDAL TRAVEL CHECK
1) Remove foot rest and displace carpet and dash silencer(s).
2) Start engine.
3) Depress brake pedal a few times.
4) With brake pedal depressed with approximately 30 kg (66 lbs)
load, measure pedal to asphalt sheet clearance ªcº.
Clearance ªcº: over 115 mm (4.53 in.)
5) If clearance ªcº is less than specification, the most possible
cause is either rear brake shoes are worn out beyond limit or air
is in lines.
Should clearance ªcº remain less than specification even after
replacement of brake shoes and bleeding of system, other pos-
sible but infrequent cause is malfunction of rear brake shoe ad-
justers or booster push rod length out of adjustment.
YH4
GRAND
VITARA
1. Parking brake lever
2. Brake cable
3. Self locking nut
5-12 BRAKES
PARKING BRAKE CHECK AND
ADJUSTMENT
CHECK
Hold center of parking brake lever grip and pull it up with 20 kg
(40 lbs) force.
With parking brake lever pulled up as shown, count ratchet
notches.
There should be 5 to 7 notches.
Also, check if both right and left rear wheels are locked firmly.
To count number of notches easily, listen to click sounds that ratchet
makes while pulling parking brake lever without pressing its button.
One click sound corresponds to one notch.
If number of notches is out of specification, adjust cable by referring
to adjustment procedure described on the following as to obtain
specified parking brake stroke.
NOTE:
Check tooth tip of each notch for damage or wear. If any dam-
age or wear is found, replace parking brake lever.
ADJUSTMENT
NOTE:
Make sure for following conditions before cable adjustment.
No air is trapped in brake system.
Brake pedal travel is proper.
Brake pedal has been depressed a few times with about
30 kg (66 lbs) load.
Parking brake lever has been pulled up a few times with
about 20 kg (44 lbs) force.
Rear brake shoes are not worn beyond limit, and self adjust-
ing mechanism operates properly.
To slacken parking brake cable, loosen self locking nut as far
as end of bolt. Then depress brake pedal a few times with
about 30 kg (66 lbs) load.
After confirming that above 6 conditions are all satisfied, adjust
parking brake lever stroke by loosening or tightening locking nut.
NOTE:
Check brake drum for dragging after adjustment.
Parking brake stroke: 5 to 7 notches
(When lever is pulled up at 20 kg (44 lbs).)
YH4
GRAND
VITARA
1. Air bleeder plug
2. Weight
3. Attachment2
ªLº
BRAKES 5-13
FLUSHING BRAKE HYDRAULIC SYSTEM
It is recommended that entire hydraulic system be thoroughly
flushed with clean brake fluid whenever new parts are installed in
hydraulic system.
Periodical change of brake fluid is also recommended.
FLUID PRESSURE TEST(if equipped with
LSPV)
Test procedure for LSPV assembly is as follows.
Before testing, confirm the following.
Fuel tank is filled with fuel fully.
Vehicle is equipped with spare tire, tools, jack and jack handle.
1) Stop vehicle on level floor and place approximately about
200 kg (441 lbs) weight on rear housing so that rear axle weight
800 kg (1764 lb).
Rear axle weight ªLº: 800 kg (1764 lb)
2) Install special tool to front and rear brake.
NOTE:
Special tool should be connected to breather of front (driv-
er's side brake) and rear brakes.
Special Tool
Front brake
(A): 09956-02310
(B): 09952-46510 (Attachment for vehicle with SUMITOMO
ELECTRIC brake caliper)
(C): 55473-82030 (Air bleeder plug supplied as a spare part)
Rear brake
(A): 09956-02310
(B): 09952-36310 (Attachment for thread diameter 7 mm of
bleeder plug) or
09952-46510 (Attachment for thread diameter 8 mm of
bleeder plug)
(C): 55473-82030 (Air bleeder plug supplied as a spare part)
NOTE:
Special tool (B) is used instead of thread diameter 10 mm
attachment of special tool (A).
So remove the attachment from (A) and install (B) as
shown in figure.
For vehicle with TOKICO brake caliper, use the attach-
ment included in special tool (A).
For identification of brake caliper type, refer to GENERAL
DESCRIPTION in SECTION 5B.
YH4
GRAND
VITARA
3. LSPV stay
1. Master cylinder
2. Disconnect brake pipe1. LSPV lever
2. LSPV spring
3, ªAº 2
1
2(a)
ªaº
ªbº
5-14 BRAKES
3) Depress brake pedal gradually till fluid pressure of front brake
becomes as specified below and check corresponding pressure
of rear brake then. It should be within specification given below.
Front brake
Rear brake
8,000 kPa
80 kg / cm2
3 Door
6,000 ± 7,300 kPa
60 ± 73 kg / cm2
853 ± 1,038 psi80 kg / cm2
1,138 psi5 Door
4,500 ± 7,300 kPa
45 ± 73 kg / cm2
640 ± 1,038 psi
As done above, apply 100 kg / cm2 pressure to front brake and
check that rear brake pressure then is within specification as giv-
en below.
Front brake
Rear brake
10,000 kPa
100 kg / cm2
3 Door
6,500 ± 8,000 kPa
65 ± 80 kg / cm2
924 ± 1,138 psi100 kg / cm2
1,422 psi5 Door
5,000 ± 8,000 kPa
50 ± 80 kg / cm2
711 ± 1,138 psi
4) If rear brake pressure is not within specification, adjust it by
changing stay ªAº position as follows.
Tightening Torque
(a): 23 N
.m (2.3 kg-m, 17.0 lb-ft)
If rear brake pressure is higher than specification, move stay
ªAº to direction ªaº and if it is lower, to direction ªbº.
Repeat steps 3) and 4) until rear brake pressure is within spec-
ification.
After adjustment, be sure to torque bolt to specification.
5) Disconnect brake pipe (connecting between master cylinder
secondary side and 4-way joint) from master cylinder.
Tighten plug (special tool) to master cylinder.
Depress brake pedal. If rear brake pressure is 95 ± 100 kg / cm
2
when front brake pressure is 100 kg / cm2, it means that front fail-
safe system functions properly.
Front brake
Rear brake
10000 kPa
100 kg / cm2
1422 psi
9500 ± 10000 kPa
95 ± 100 kg / cm2
1350 ± 1422 psi
Special Tool
(A): 09956-02210