ABS ISUZU TROOPER 1995 Service Manual

l•!•l DISASSEMBLY
•
•
•
Jack up the vehicle and support it using jack
stands.
Remove the
tire and wheel.
Remove the drain bolt to drain differential oil.
NOTE:
•
During the work, be sure that the diff case is
supported by the jack (Fig. 4C-7).
Fig.
4C-7
• Remov: the brake caliper fixing bolt and hang
the caliper. Refer to Section 5A2 "DISC
BRAKES".
•
Remove the antilock brake system speed
sensor.
(If equipped with antilock brake
system) Refer
to Section 5A4 "4-WHEEL ANTI­
LOCK
BRAKE SYSTEM (ABS)".
1. Hub assembly (Disc, back plate and knuckle)
• Remove the locking hub. Refer to this Section
"FRONT HUB AND DISC".
•
Disconnect the knuckle and the suspension
arm. Refer
to Section 3C "FRONT SUSPEN­
SION".
2. Steering link and arm assembly
• Refer to Section 3B3 "STEERING LINKAGE".
3. Suspension crossmember
4. Propeller shaft
• Refer to Section 4A "PROPELLER SHAFT".
5. Mounting bolt and nut (Fig. 4C-8)
FRONT DRIVING AXLE 4C-7
Fig. 4C-8
6. Washer and spacer
7. Bolt (Fig. 4C-9)
• Remove the mounting bracket fixing bolt.
Fig. 4C-9
8. Front axle case assembly and front drive shaft
assembly (LH side) (Fig. 4C-10)
• Lower the vehicle and disconnect the RH front
drive shaft assembly, and then remove the
front axle case assembly and front drive shaft
assembly (LH).
Fig. 4C-10

.
fi•28 FRONT DRIVINGk "
;: ~ ·~-¢,,
FRONT HUB AND D1SC (4WD Model with Automatic Locking Hub)
Disassembly steps 1. Bolt
2. Hub cap 3. Housing
4. Snap ring and shim
5. Drive clutch assembly 6. Inner cam assembly
7. Lock washer and lock screw 8. Hub nut
9. Hub and disc assembly 10. ABS sensor ring
11. Outer bearing outer race 12. Oil seal
13. Inner bearing outer race 14. Bolt
15. Wheel pin
Fig. 4C-72
10
9
Reassembly steps 15. Wheel pin 14. Bolt 13. Inner bearing outer race 11. Outer bearing outer race
12. Oil seal 10. ABS sensor ring 9. Hub and disc assembly 8. Hub nut 7. Lock washer and lock screw
6. Inner cam assembly 5. Drive clutch assembly 4. Snap ring and shim 3. Housing
2. Hub cap 1. Bolt
'
.f,
c. ' . .,;
)
t
~::
•

1•! .. 1 DISASSEMBLY
•
Shift the transfer lever to the "2H" position and
move the vehicle forward and rearward about
one meter.
• Remove the 14mm hex bolts.
• Before disassembly, jack up the front of vehicle
and
support frame with jack stands.
• Remove the disc brake caliper assembly and
hang
it on the frame with wires. Refer to Section
5A2
"DISC BRAKES".
1. Bolt (Fig. 4C-73)
Fig. 4C-73
2. Hub cap
3. Housing
4. Snap ring and shim
5. Drive clutch assembly
6. Inner cam assembly
7. Lock washer and lock screw
8. Hub nut (Fig. 4C-74)
1®.1 Wrench: J-36827
Fig. 4C-74
Front hub nut wrench (J-36827)
FRONT DRIVING AXLE 4C-29
9. Hub and disc assembly
10. ABS
sensor ring (if so equipped)
11.
Outer bearing outer race
12.
Oil seal
13. Inner bearing outer race
1) Remove the outer bearing from the hub with
fingers. The inner bearing will remain in the
hub and may be removed after prying out the
inner bearing lip seal assembly (Fig. 4C-75).
2) Remove the outer race by driving out the
race from the hub with a brass drift inserted
behind
the race in the notches in the hubs.
Inner bearing
outer race
Fig. 4C-75
14.
Bolt (Fig. 4C-76)
• If necessary, replace the wheel pin in the
following manner.
1) Apply a scribe mark to disc to hub.
2) Clamp the hub and disc assembly in a vise,
using protective pads. Remove
the 6 disc­
to-hub retaining bolts.
Scribe mark
Fig. 4C-76

4C -30 FRONT DRIVING AXLE
15. Wheel pin (Fig. 4C-77)
• Place
hub on a suitable work surface and
remove the
wheel studs, as required, using a
hammer.
Fig. 4C-77
I L•IINSPECTION AND REPAIR
Make necessary correction or parts replacement if
wear, damage, corrosion or any other abnormal
condition are found through inspection.
Check
the following parts.
• Hub
• Hub bearing oil seal
• Knuckle spindle
•
Disc
• Caliper
•
Automatic locking hubs
• ABS sensor ring
For inspection and servicing
of disc caliper and
related parts, refer to Section 5A2 "DISC BRAKES".
rfil Inside diameter of housing measurement (Fig.
~ 4C-78)
mm(in)
Standard Limit
65.04 (2.561)
65.24 (2.568)
Inspect flange surface A and 8 for excessive wear.
A ---....
1 I
'-/ I
i/ 8mm (Measuring point) I I
~.
e
Fig. 4C-78
rfil Drive clutch section
~ measurement (Fig. 4C-79)
Standard
8.2 (0.323)
L
Fig. 4C-79 dimensions
ulu
mm(in)
Limit
7.8
(0.307)
1@ 1 Hold ring sliding resistance check (Fig. 4C-80)
Check the sliding resistance along opening
direction as shown in the figure.
N (lb)
Sliding Resistance 16.7-34.3 (3.8-7.7)
......
Fig. 4C-80

4C-32 FRONT DRIVING AXLE
11. Outer bearing and outer race (Fig. 4C-86)
li5\l • Install the outer race; outer bearing by driving it
L::!iil into the hub.
Installer: J-36828
Grip: J-8092
Fig. 4C-86
12. Oil seal (Fig. 4C-87)
r::::l • Place the inner bearing onto the outer race in
D the hub and install a new oil seal and retaining
~. ring.
Apply Besco L-2 or equivalent to the lip portion.
Installer: J-36830
Grip: J-8092
Fig. 4C-87
10. ABS sensor ring (if so equipped)
~~~ Torque N·m (lb·ft) [ 18 (13)
9. Hub and disc assembly (Fig. 4C-88)
r::::l 1) Put grease in the hub.
D 2) Place Besco L-2 or equivalent to the outer and
inner bearing.
g (oz)
Hub 35 (1.23)
Outer bearing 10 (0.35)
Inner bearing 15 (0.53)
Outer bearing Inner
bearing
Fig. 4C-88
8. Hub nut (Fig. 4C-89)
r=1 • Install the nut with the chamfered edge of
~ inside diameter outward.
1®..1 Wrench: J-36827
Front hub nut wrench (J-36827)
Fig. 4C-89
IEEI Preload adjustment (Fig. 4C-90)
Tighten the hub nut to 29.4 N·m (21.7 lb·ft), then
loosen the
nut fully.
Tighten the hub nut to reach the bearing preload
given below, using a spring scale on the wheel
pin.
Bearing
Preload
New bearing and
New oil seal
Used bearing and
New
oil seal
19.6-24.5
(4.4-5.5)
11.8-17.7
(2.6-4.0)
N (lb)
If the measured bearing preload is outside the
specifications, adjust
it by loosening or tightening
the bearing nut.
•

HYDRAULIC BRAKES SA-1
BRAKES
w CAUTION:
• All
brake attaching fasteners are an important attaching part in that they could affect performance of vital
parts and systems, and/or could result in major repair expense. They must be replaced with one of the same
part
number or with an equivalent part if replacement becomes necessary. Do not use replacement parts of
lesser quality or substitute design. Torque values must be used as specified during reassembly to assure
proper retention
of these parts.
CONTENTS
Hydraulic Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section SA
Brake Booster System ........................................................ Section 5A1
Disc Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section 5A2
Rear
Wheel Antilock Brake System (RWAL) .................................... Section 5A3
4-Wheel Antilock Brake System (ABS) ......................................... Section 5A4
Parking Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Section 5C
SECTION 5A
HYDRAULIC BRAKES
CONTENTS
Brake System Diagnosis ................ SA-2
Road
Testing the Brakes . . . . . . . . . . . . . . SA-2
Brake
Fluid Leaks . . . . . . . . . . . . . . . . . . . . SA-2
Warning Light Operation . . . . . . . . . . . . . SA-2
Antilock Brake System (RWAL or ABS) . SA- 2
Diagnosis of Brake System . . . . . . . . . . . . . . SA-3
On-Vehicle Service .................... SA- S
Filling Master Cylinder Reservoir . . . . . . . SA-S
Deterioration of Brake Fluid . . . . . . . . . . . SA-S
Leakage
of Brake Fluid . . . . . . . . . . . . . . . SA-S
Bleeding Brake Hydraulic System . . . . . . SA-S
Flushing Brake Hydraulic System . . . . . . SA-6
Brake Pipes
and Hoses . . . . . . . . . . . . . . . SA-6
Brake Hose
Inspection . . . . . . . . . . . . . . . SA-6
Brake Hose
Replacement . . . . . . . . . . . . . SA-7
Brake Pipe
Replacement . . . . . . . . . . . . . . SA-8
Combination Valve/P & B Valve . . . . . . . SA-9
Valve Replacement . . . . . . . . . . . . . . . . . . SA-1 0
Inspection of Brake Pad Lining . . . . . . . . SA-11
Inspection of Brake Rotors . . . . . . . . . . . . SA-11
Brake Pedal Assembly .................. SA-13 •
Checking Pedal Height ................ SA-13
Checking Pedal Travel ................ SA-13
Brake
Pedal Replacement ............. SA-14
Stoplight Switch Replacement ......... SA-1S
Master Cylinder Assembly ............... SA-16
General Description .................. SA-16
On-Vehicle Service ................... SA-17
Unit Repair .......................... SA-19
Main Data and Specifications ............ SA-21
General Specifications ................ SA-21
Torque Specifications ................ SA-21
Special Tools .......................... SA-22

SA-2 HYDRAULIC BRAKES
BRAKE SYSTEM DIAGNOSIS
ROAD TESTING THE BRAKES
Brake Test
Brakes should be tested on a dry, clean, reasonably
smooth and
level roadway. A true test of brake
performance cannot be made
if the roadway is
wet, greasy
or covered with loose dirt so that all
tires do not grip the road equally. Testing will also
be adversely affected if the roadway is crowned so
as to throw the weight of the vehicle toward
wheels on one side or if the roadway is so rough
that wheels tend to bounce. Test the brakes at dif­
ferent vehicle speeds with both light and heavy
pedal pressure; however, avoid locking the wheels
and sliding the tires. Locked wheels and sliding
tires do not indicate brake efficiency, since heavily
braked but turning wheels will stop the vehicle in
less distance than locked wheels. More tire-to-road
friction is present
with a heavily braked turning tire
then
with a sliding tire.
The standard brake system is designed and
balanced
to avoid locking the wheels except at very high
deceleration
levels.
It
is designed this way because the shortest stopping
distance and best
control is achieved without brake
lock-up.
Because of high deceleration capability, a firmer pedal
may be felt at higher deceleration levels.
External Conditions That Affect Brake
Performance
1.
2.
3.
Tires: Tires having unequal contact and grip on
the road
will cause unequal braking. Tires must
be equally inflated, identical in size, and the tread
pattern
of right and left tires must be approxi­
mately equal.
Vehicle loading:
A heavily loaded vehicle requires
more braking effort.
Wheel Alignment: Misalignment of the wheels,
particularly
in regard to excessive camber and
caster,
will cause the brakes to pull to one side.
BRAKE FLUID LEAKS
With engine running at idle and the transmission in
"Neutral", depress the brake pedal and hold a constant
foot pressure on the pedal. If pedal gradually falls
away with the constant pressure, the hydraulic system
may be leaking.
Check the master cylinder fluid level. While a slight
drop in reservoir level will result from normal lining
wear, an abnormally low level in reservoir indicates a
leak in the system. The hydraulic system may be
leaking internally as well as externally. Refer to
"Master Cylinder Inspection". Also, the system may
appear
to pass this test but still have slight leakage. If
fluid level
is normal, check the vacuum booster
push rod
length. If an incorrect length push rod is
found, adjust
or replace the push rod. Check the
brake
pedal travel and the parking brake adjust­
ment.
When checking the
fluid level, the master cylinder fluid
level
may be low from the "MAX" mark if the front and
rear
linings are worn. This is not abnormal.
WARNING LIGHT OPERATION
When the ignition switch is in the START position,
the
"BRAKE" warning light should glow and go off
when the ignition switch returns to the ON position.
The
following conditions will activate the "BRAKE"
light:
1. Parking brake applied. The light should be on
whenever the parking brake is applied and the
ignition switch is on.
2. Low fluid level. A low fluid level in the master
cylinder will turn the "BRAKE" light on (Except
Rear
Wheel Antilock Brake System (RWAL)
model).
3. During engine cranking the "BRAKE" light
should
remain on. This notifies the driver that
the warning circuit is operating properly.
4. In the event of a front or rear system malfunc­
tion (RWAL model only).
5. In the event of RWAL malfunction (RWAL
model only. Refer to Section 5A3).
ANTILOCK BRAKE SYSTEM (RWAL or
ABS}
Refer to Section 5A3 or 5A4 for inspection and di­
agnosis procedure of the hydraulic unit.
..

HYDRAULIC BRAKES 5A-5
ON-VEHICLE SERVICE
FILLING MASTER CYLINDER
RESERVOIR
'\fl CAUTION:
'VI • Use only specified brake fluid. Do not use any
fluid which contains a petroleum base. Do not
use a container which has been used for
petroleum based fluids or a container which is
wet with water. Petroleum based fluids will
cause swelling and distortion of rubber parts in
the
hydraulic brake system. Water mixed with
brake fluid lowers the fluid boiling point. Keep
all fluid containers capped to prevent contami­
nation.
• Always fill the master cylinder reservoir when
the engine is
cold.
•
Never allow the brake fluid to come in contact
with the painted surfaces.
The master
cylinder reservoir must be kept properly
filled
to ensure adequate reserve and to prevent air
and moisture
from entering the hydraulic system.
However, because
of expansion due to heat absorbed
from the brakes and the engine, the reservoir must not
be overfilled. The brake fluid reservoir is on the master
cylinder, which is located under the hood on the
left
side of the cowl. Thoroughly clean reservoir cap
before
removal to avoid getting dirt into reservoir.
Remove cap and diaphragm.
Add fluid as required to
bring level to the "MAX" mark on the reservoir tank.
Use
"DOT 3" Hydraulic Brake Fluid. If the fluid cap
diaphragm is stretched, return
it to the original position
before
installing.
DETERIORATION OF BRAKE FLUID
Using any other brake fluid than specified or brake fluid
with mineral oil or water mixed in will drop the boiling
point of brake fluid. It may, in turn, result in vapor lock
or deteriorated rubber parts of the hydraulic system.
Be sure to change brake fluid at specified intervals.
If rubber parts are deteriorated, remove all the system
parts and
clean them with alcohol. Prior to reassembly,
dry the cleaned parts with air to remove the alcohol.
Replace all
hoses and rubber parts of the system.
LEAKAGE OF BRAKE FLUID
With engine idling, set shift lever in the neutral position
and continue to depress brake
pedal at a constant
pressure.
Should the pedal stroke become deeper gradually,
leak from the hydraulic pressure system is possible.
Make sure
by visual check that there is no leak.
BLEEDING BRAKE HYDRAULIC SYSTEM
A bleeding operation is necessary to remove air from
the hydraulic brake system whenever air is introduced
into the hydraulic system.
It may be necessary to bleed
the hydraulic system at all four brakes if air has been
introduced through a
low fluid level or by dis­
connecting brake pipes at the master cylinder. If a
brake pipe is disconnected at one
wheel, only that
wheel cylinder/caliper needs to be bled. If pipes are
disconnected at any fitting
located between master
cylinder and brakes, then the brake system served by
the disconnected pipe must
be bled.
1. For 4-wheel Antilock Brake System (ABS)
equipped
vehicle, be sure to remove the ABS
main fuse
40A located at the relay and fuse box
before
bleeding air. If you attempt to bleed air
without removing the main fuse, air cannot be let
out thoroughly, and this may cause damage to the
hydraulic unit.
After bleeding air, be sure to
replace the ABS main fuse back to its original
position.
2. Set the parking brake completely, then start the
engine.
NOTE:
The vacuum booster will be damaged if the
bleeding operation is performed with the engine
off.
3. Remove the master cylinder reservoir cap.
4. Fill the master cylinder reservoir with brake fluid.
Keep the reservoir at least half full during the air
bleeding operation.
5. Always use new brake fluid for replenishment.
6. In replenishing brake fluid, take care that air
bubbles do not enter the brake fluid.
•
When the master cylinder is replaced or
overhauled, first bleed the air from the master
cylinder, then from each
wheel cylinder and
caliper following the procedures described
below.
Bleeding the master cylinder (Fig. 5A-1}
7. Disconnect the rear wheel brake pipe master
cylinder (Fig. 5A-1 ). Check the fluid level
and replenish as necessary. If replenished, leave
the system for at least one minute.
8. Depress the brake pedal slowly once and hold it
depressed.
9. Completely seal the delivery port of the master
cylinder where the pipe was disconnected with
your finger, then release the brake pedal slowly.
10. Release your finger from the delivery port when
the brake
pedal returns completely.
11. Repeat steps 7 through 9 until the brake fluid
comes out of the delivery port during step 7.

REAR WHEEL ANTILOCK BRAKE SYSTEM 5A3-7
REAR WHEEL ANTILOCK (RWAL) SYSTEM DIAGNOSTICS
DIAGNOSIS PROCEDURE
The RWAL system contains 13 diagnostic trouble
codes
for system troubleshooting. With the ignition
key turned
ON, momentarily grounding the RWAL
diagnostic lead
with the "Rr ABS" light on will cause the
light
to flash out a diagnostic trouble code if a failure
has been detected and is in memory.
Some RWAL
diagnostic trouble codes require a road test in order
to
be set into the EBCM memory.
RWAL diagnostic trouble codes are cleared from
the
EBCM memory every time the ignition key is
turned off. If a diagnostic trouble code is not present, a
test drive
must be performed to reproduce the failure
and reset the code into
memory:
TEST DRIVING
1. Conduct a visual check of the following items to
see if any abnormalities exist:
(a) Service brake mechanism/hydraulic system
(See BRAKE SERVICING SECTION).
(b) Fuses #2, #7, #14 and main fuse
(c) RWAL-related connector (check for loose pins
and rust)
(d) EBCM and valve ground (check for looseness
and rust)
NOTE:
Check
(c) and (d) should be done with ignition key
turned
OFF.
If any abnormality is found, perform repairs as
required.
2. Turn the ignition switch ON. As a self-check, the
"Rr ABS" light should come on for approximately
2 seconds, then go
off and remain off.
If the "Rr ABS" light remains on or comes back
on, check
for diagnostic trouble codes by
momentarily grounding the RWAL diagnostic
lead
with the "Rr ABS" light on. -
If the "Rr
ABS" light self-check operates
properly, continue
with the test drive below.
3. Test driving vehicle:
(a) Start the engine and begin driving the vehicle.
(b) Accelerate to 40 mph.
(c) At least once, brake to a full stop using enough
brake pedal force
to activate the RWAL
system.
(d) Accelerate to 60 mph and continue to run at
this speed
for 5 minutes.
4. If a diagnostic trouble code is obtained.
inspect in accordance
with the appropriate
"FLASHOUT DIAGNOSTIC TROUBLE CODES
CHART".
If
no diagnostic trouble code is found, and the
"Rr ABS" and "BRAKE" light comes on, or if
any abnormal operation occurs during the
test drive, inspect in accordance
with CHART
C, "Rr ABS AND BRAKE LIGHTS ON".
5. If the "Rr ABS" or "BRAKE" light does not come
during the test drive, ask the customer under
what conditions the light came on. Then try to
duplicate the complaint condition
as closely as
possible.
If no problem is found, check all underhood
connections that supply power
to the RWAL and
ignition fuses, inspect
all RWAL harness
connectors, and inspect the
EBCM and anti-lock
valve ground connections.
Do not assume that the
EBCM is bad because the
"Rr ABS" or "BRAKE" lights are on. In most cases,
it is telling you it has found a problem elsewhere.
Fig. 5A3-7

5A3-8 REAR WHEEL ANTILOCK BRAKE SYSTEM
How to read diagnostic trouble codes
Count the number of short flashes starting from the
long flash. Include the long flash as a count. Some­
times the first count sequence is short because the
flashout started with the count already in progress.
Subsequent counts, however, will be accurate. If there
is more than one system
failure, only the first
recognized diagnostic code
will be retained in memory
and flashed. If a diagnostic code is obtained, go to the
appropriate
flashout code chart.
DIAGNOSTIC CODE : Rr. ABS LIGHT IS ON AND OFF.
SIGNAL CODE 3
0.2 0.2 I I !Sec. I !Sec.! r--1.4 Seconds --+j ~ t--1
ON-------,~-----------,--~--~~~-r--?-----------~--r--r-----
OFF ~' ----L-1--'-----11 IL....-l.-1 ~I I ______..l__.__l ..____I
0.2~ ~ ~
-Sec.
Count #1 #2 #3 r----~ Repeat---
Fig. 5A3-8
Refer
to Charts A through E if a diagnosis code cannot
be obtained and any
of the following light conditions
are observed:
"Rr ABS" light off but no 2 second bulb
self
check; "BRAKE" light on and "Rr ABS" light off;
both
"Rr ABS" and "BRAKE" lights on or flashing.
Be sure to perform all conventional brake system
diagnosis before assuming the
problem is in the rear
wheel antilock system.
NOTE:
After a repair has been completed from Charts A
through
E, the power to the module does not have to be
broken to
clear the memory, as these failures are not
stored in memory.
NOTE:
Do not assume the EBCM is bad because the "Rr ABS"
and "BRAKE" lights are on. In most cases, it is telling
you it has found a problem elsewhere.
REAR ABS AND BRAKE LIGHTS CHART
CONDITION ACTION TO TAKE
Rr. ABS light "OFF" and will not self-check.
See CHART A
BRAKE light "ON" Rr. ABS light "OFF" and does self-check.
See CHART B
Rr. ABS and BRAKE lights "ON"
See CHART C
Rr. ABS and BRAKE lights flashing.
See CHART D
Rear
wheels lock with hard stops. See CHART E (Rr. ABS and BRAKE lights self check properly.)