brake fluid ISUZU TROOPER 1998 Service Repair Manual
[x] Cancel search | Manufacturer: ISUZU, Model Year: 1998, Model line: TROOPER, Model: ISUZU TROOPER 1998Pages: 3573, PDF Size: 60.36 MB
Page 16 of 3573
GENERAL REPAIR INSTRUCTIONS
1. Park the vehicle on level ground and chock the
front or rear wheels before lifting the vehicle.
2. Use covers on the vehicle body, seats, and
floor to prevent damage and/or
contaminations.
3. Disconnect the grounding cable from the
battery before performing service operations.
This will prevent cable damage or burning due
to shortcircuiting.
4. Raise the vehicle with a jack set against the
recommended lifting points (see ÒLifting
instructionsÓ in this section).
5. Support the vehicle on chassis stands.
6. Handle brake fluid and antifreeze solution with
great care.
Spilling these liquids on painted surfaces will
damage the paint.
7. The use of the proper tool(s) and special tool(s)
where specified is essential to efficient,
reliable, and safe service operations.
8. Always use genuine ISUZU replacement parts.
9. Discard used cotter pins, gasket, plastic clips,
O-rings, oil seals, lock washers, and self-
locking nuts at disassembly.
Normal function of these parts cannot be
guaranteed if they are reused.
10. Keep the disassembled parts neatly in groups.
This will facilitate smooth and correct
reassembly.11. Keep fixing nuts and bolts separate.
Fixing nuts and bolts vary in hardness and
design according to installation positions.
12. Clean all parts before inspection or
reassembly.
13. Clean the oil ports and other openings with
compressed air to make certain that they are
free of dirt and obstructions.
14. Lubricate the rotating and sliding faces of all
moving parts with oil or grease before
installation.
15. Use the recommended liquid gasket to prevent
leakage.
16. Carefully observe all nut and bolt torque
specifications.
17. When service operation is completed, make a
final check to be sure service has been done
properly and problem has been corrected.
18. When removing or replacing parts that require
refrigerant to be discharged from the air
conditioning system, be sure to use the
following tools to recover and recycle the
Refrigerant-134a (R-134a).
For 134a:
Use the R-134a Refrigerant Recovery/Recovery/
Recycling/Recharging/System (ACR
4) or its
equivalent to prevent the discharge of
refrigerant into the air.
0AÐ2 GENERAL INFORMATION
Page 29 of 3573
0BÐ2 MAINTENANCE AND LUBRICATION
MAINTENANCE SCHEDULE
GASOLINE ENGINE MODELI: Inspect and correct or replace as necessary A: Adjust
R: Replace or change T: Tighten to specified torque L: Lubricate
SERVICE INTERVAL: x 1,000 km
(Use odometer reading x 1,000 miles
or months whichever comes first) or months5
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1215
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1820
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2425
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3030
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3635
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4240
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4845
27
5450
30
6055
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6660
36
7265
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7870
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8475
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9080
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9685
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10290
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10895
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114100
60
120
GASOLINE ENGINE
* Engine oil
* Engine oil filter
Oil leakage and contamination
* Timing belt
Spark plugs (For leaded fuel use)
Spark plugs (For unleaded fuel use)
Exhaust system
Radiator coolant concentration
Cooling system for water leakage
All hoses and pipes in engine compartment
for clog or damage
Fuel filter
Fuel leakage
Fuel tank
* Air cleaner element
Pre air cleaner
Engine drive belt
Valve clearance
O
2 Sensor (For leaded fuel use)
O
2 Sensor (For unleaded fuel use)-
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(Replace every 165,000 km or 100,000 miles)
(Replace every 165,000 km or 100,000 miles)
(Check and adjust if necessary every 100,000 km or 60,000 miles)
(Replace every 150,000 km or 90,000 miles)
CLUTCH
Clutch fluid
Clutch pedal travel and free play
TRANSMISSION OR TRANSMISSION WITH
TRANSFER CASE
* Manual transmission with transfer case oil
* Automatic transmission fluid leakage
*
(1)Automatic transmission fluid
* Transfer case oil
PROPELLER SHAFT
Loose connections
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Universal joints and splines for wear
Universal joints and sliding sleeve (front and rear)
FRONT AND REAR AXLE
* Differential gear oil (Front and rear)
Shift on the fly system gear oil
Front axle shaft rubber boot for damage
Axle case for distortion or damage
Axle shafts for distortion or damage-
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ATATAT
STEERING
* Power steering fluid
Oil leakage
* Steering system for looseness or damage
Power steering hose
Steering wheel play
Steering function
Right and left turning radius
Wheel alignment
Joint ball for oil leakage or damage
Joint ball rubber boot for damage
SERVICE BRAKES
Brake fluid
Brake system for fluid leakage
Brake function
* Disc brake pads and discs wear
Brake pedal travel and free play
Pipes and hoses for loose connections or damage
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(1): Adjust or change automatic transmission fluid.
*Marks: Under severe driving conditions, additional maintenance is required.
Refer to “Maintenance schedule under severe driving conditions”.
Page 31 of 3573
0BÐ4 MAINTENANCE AND LUBRICATION
DIESEL ENGINE MODELI: Inspect and correct or replace as necessary A: Adjust
R: Replace or change T: Tighten to specified torque L: Lubricate
SERVICE INTERVAL: x 1,000 km
(Use odometer reading x 1,000 miles
or months whichever comes first) or months5
3
610
6
1215
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1820
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2425
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3030
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3635
21
4240
24
4845
27
5450
30
6055
33
6660
36
7265
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7870
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8475
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9080
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9685
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10290
54
10895
57
114100
60
120
DIESEL ENGINE
* Engine oil
* Engine oil filter
Oil leakage and contamination
Idling speed and acceleration
Fan belt tension and damage
Timing belt
Exhaust system
All hoses and pipes in engine compartment
for clog or damage
Valve clearance
* Air cleaner element
Fuel filter
Radiator coolant concentration
Cooling system for water leakage-
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NOTE: In the 4JXI-TC diesel engine, there is provided sub (2nd) oil filter for fuel injection at the upper part of crank case on the left
side of the engine. This oil filter maintenance-free and does not need a periodic replacement. See reverse side the (back)
cover for installation location of the sub (2nd) oil filter.(Replace every 200,000 km or 125,000 miles)
*Marks: Under severe driving conditions, additional maintenance is required.
Refer to “Maintenance schedule under severe driving conditions”. CLUTCH
Clutch fluid
Clutch pedal travel and free play
TRANSMISSION OR TRANSMISSION WITH
TRANSFER CASE
* Manual transmission with transfer case oil
* Automatic transmission fluid
* Transfer case oil
PROPELLER SHAFT
Loose connections
* Universal joints and splines for wear
Universal joints and sliding sleeve (front and rear)FRONT AND REAR AXLE
* Differential gear oil (Front and rear)
Shift on the fly system gear oil
Front axle shaft rubber boot for damage
Axle case for distortion or damage
Axle shafts for distortion or damage-
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ATAT
STEERING
* Power steering fluid
Oil leakage
* Steering system for looseness or damage
Power steering hose
Steering wheel play
Steering function
Right and left turning radius
Wheel alignment
Joint ball for oil leakage or damage
Joint ball rubber boot for damage
SERVICE BRAKES
Brake fluid
Brake system for fluid leakage
Brake function
* Disc brake pads and discs wear
Brake pedal travel and free play
Pipes and hoses for loose connections or damage
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Page 33 of 3573
0BÐ6 MAINTENANCE AND LUBRICATION
Item IntervalCondition
ABCD A+D
Engine oil G : Change every 5,000 km (3,000 miles)
D : Change every 5,000 km (3,000 miles) ll
Engine oil filter G : Replace every 10,000 km (6,000 miles)
D : Replace every 5,000 km (3,000 miles) ll
Air cleaner element G : Replace every 20,000 km (12,000 miles)
D : Replace every 40,000 km (25,000 miles)l
Power steering fluid Replace every 50,000 km (30,000 miles)ll
Steering system for looseness
or damage Inspect every 5,000 km (3,000 miles)l
Universal joints and sleeves Inspect for wear and lubricate every 7,500 km (4,500 miles)ll
Transmission with MT Change every 20,000 km (12,000 miles)
transfer case oil after changing at initial 10,000 km (6,000 miles)l
Transmission :
AT
Change every 32,000 km (20,000 miles) lll l
Transfer:
TF Change every 20,000 km (12,000 miles)
after changing at initial 10,000 km (6,000 miles)l
Differential oil Change every 20,000 km (12,000 miles)
after changing at initial 5,000 km (3,000 miles) l
Disc brake pads and discs Inspect every 5,000 km (3,000 miles)lll
Timing belt G : Replace every 120,000 km (75,000 miles)ll
EXPLANATION OF COMPLETE VEHICLE MAINTENANCE SCHEDULE
Explanations of the services listed in the proceeding
Maintenance Scheduled are presented in ÒService
InformationÓ section of each manual.Replace all questionable parts and note any
necessary repairs as you perform these
maintenance procedures.
MAINTENANCE SCHEDULE UNDER SEVERE DRIVING CONDITIONS
Severe driving conditions
A: Repeated short trips
B: Driving on rough roads
C: Driving on dusty roads
D: Driving in extremely cold weather and/or salted roads
Page 35 of 3573
0BÐ8 MAINTENANCE AND LUBRICATION
FLUID TYPE
Clutch and brake fluid reservoir Besco brake fluid (For light duty)
Hydraulic brake fluid SAE J1703
FMVSS 116 DOT.3 grade
LUBRICATION MAKE BRAND / TYPEGRADE
API ACEA
ISUZU GENUINE BESCO ATF II, ATF III
EXXON / ESSO ESSO ATF D (DEXRONÒ
II-D)
Automatic transmission MOBIL MOBIL ATF (DEXRONÒ
III)
Power steering CALTEX ATF HD (DEXRONÒ
II)
SHELL SHELL DONAX TA (DEXRONÒ
II-D)
ELF ELFMATIC G3 (DEXRONÒ
III)
TOTAL TOTAL FLUID IID (DEXRONÒ
II-D)
ISUZU GENUINE
BESCO L-2 GREASE (No.2), L-3 GREASE (No.3)Propeller shaft sliding EXXON / ESSO RONEX MP (No.2)
yoke, Universal joint MOBIL MOBILGREASE HP 222 (No.2)
Grease fittingCALTEX / TEXACOSTARPLEX-2 (No.2)
(General purpose grease)SHELL SHELL RETINAX A (No.2)
TOTAL MULTIS EP2, EP3 (No.2, No.3)
Propeller shaft slidingISUZU GENUINE ONE LUBER MO GREASE
yoke EXXON / ESSO BEACON Q2 (No.2)
Universal joint EXXON / ESSO MULTIPURPOSE GREASE (Moly) (No.2)
General purpose greaseCALTEX MOLYTEX GREASE EP2 (No.2)(in Molybdenum)TOTAL TOTAL MULTIS MS2 (No.2)
ISUZU GENUINE BESCO LLC SUPER TYPE E
TEXACO / CALTEX HAVOLINE EXTENDED LIFE ANTIFREEZE
Engine cooling system COOLANT
HAVOLINE XLC
EXTENDED LIFE COOLANT 6280
NOTE:
When the recommended lubricants are specified in the workshop manual, follow them.
Page 289 of 3573
SERVICE INFORMATION 00 – 7
Problem Possible Cause Correction
POWER STEERING SYSTEM
HISSING NOISE
There is some noise in all power steering systems. One of the most common is a hissing sound when the
steering wheel is fully turned and the car is not moving. This noise will be most evident when the wheel is
operated while the brakes are applied. There is no relationship between this noise and steering
performance. Do not replace the valve unless the "hissing" noise is extremely objectionable. A replacement
valve will also have a slight noise, and is not always a cure for the condition.
Rattle or Chucking Noise
Poor Return of Steering
Wheel to Center
Momentary Increase in
Effort When Turning
Wheel Fast to Right or
Left
Steering Wheel Surges or
Jerks When Turning
Especially During Parking
Excessive Wheel Kick
Back or Loose Steering
Hard Steering or Lack of
Power Assist1. Pressure hose touching other parts of
vehicle.
2. Tie rod ends loose.
3. Loose steering gear mounting.
4. Steering gear misadjustment.
1. Improper front wheel alignment.
2. Wheel bearing worn.
3. Tie rod end binding.
4. Ball joint binding.
5. Tight or frozen steering shaft bearing.
6. Steering gear misadjustment.
7. Sticky or plugged steering gear valve.
8. Entry of air in the power steering
system.
1. High internal leakage.
2. Power steering fluid level low.
1. Insufficient pump pressure.
2. Sticky steering gear valve.
3. Power steering fluid level low.
1. Air in system.
2. Tie rod end loose.
3. Wheel bearing worn.
1. Sticky steering gear valve.
2. Insufficient pump pressure.
3. Excessive internal pump leakage.
4. Excessive internal steering gear
leakage.
5. Power steering fluid level low.Adjust hose position. Do not
bend tubing by hand.
Tighten or replace tie rod end.
Tighten steering gear
mounting.
Check and adjust steering gear
preload.
Adjust front wheel alignment.
Replace front wheel bearing.
Replace tie rod end.
Replace ball joint.
Replace steering assembly.
Adjust the steering gear.
Repair or replace steering gear
valve.
Bleed the system.
Repair steering gear.
Replenish fluid.
Repair pump assembly.
Repair or replace steering gear.
Replenish fluid.
Bleed hydraulic system.
Tighten tie rod end.
Replace wheel bearing.
Repair or replace steering gear
valve.
Repair pump assembly.
Repair pump assembly.
Repair steering gear.
Replenish fluid.
Page 471 of 3573
4A2A±4
DIFFERENTIAL (REAR 220mm)
Axle Housing
Axle Housing and Associated Parts
420RW022
Legend
(1) Coil Spring and Insulator
(2) Axle Housing Assembly
(3) ABS Speed Sensor and Harness(if equipped)
(4) Nut
(5) Parking Brake Cable
(6) Bolt and Nut
(7) Antilock Brake System (ABS) Connector and
Bracket (if equipped)
(8) Bolt and Nut(9) Nut
(10) Differential Assembly
(11) Axle Shaft Assembly
(12) Brake Disc
(13) Brake Pipe
(14) Brake Caliper
(15) Nut
(16) Breather Hose
(17) Flare Nut
Removal
1. Raise the vehicle and support it with suitable safety
stands.
The hoist must remain under the rear axle housing.
2. Drain brake fluid. Refer to Hydraulic Brakes in Brake
section.
3. Remove rear wheels and tires. Refer to Wheel in
Suspension section.4. Remove propeller shaft. Refer to Rear Propeller
Shaft in this section.
5. Drain the rear axle oil into a proper container.
6. Remove parking brake cable, release the connection
between the cable fixing clip equalizer. Refer to
Parking Brakes in Brake section.
7. Move the clip aside and pull out the breather hose.
Page 507 of 3573
4A2B±4DIFFERENTIAL (REAR 244mm)
Axle Housing
Axle Housing and Associated Parts
420RW001
Legend
(1) Coil Spring and Insulator
(2) Axle Housing Assembly
(3) ABS Speed Sensor and Harness (if so
equipped)
(4) Nut
(5) Parking Brake Cable
(6) Bolt and Nut
(7) Antilock Brake System (ABS) Connector and
Bracket (if so equipped)(8) Bolt and Nut
(9) Nut
(10) Differential Assembly
(11) Axle Shaft Assembly
(12) Brake Disc
(13) Brake Pipe
(14) Brake Caliper
(15) Nut
(16) Breather Hose
(17) Flare Nut
Removal
1. Raise the vehicle and support it with suitable safety
stands.
The hoist must remain under the rear axle housing.
2. Drain brake fluid. Refer to Hydraulic Brakes in Brakes
section.
3. Remove rear wheels and tires. Refer to Wheel in
Suspension section.4. Remove propeller shaft. Refer to Rear Propeller
Shaft in this section.
5. Drain the rear axle oil into a proper container.
6. Remove parking brake cable, release the connection
between the cable fixing clip equalizer. Refer to
Parking Brakes in Brakes section.
7. Move the clip aside and pull out the breather hose.
Page 814 of 3573
5A±4
BRAKE CONTROL SYSTEM
normal braking when a malfunction has occurred in the
ABS.
The EHCU has a self-diagnosing function which can
indicate faulty circuits during diagnosis.
The EHCU is mounted on the engine compartment front
right side. It consists of a Motor, Plunger Pump, Solenoid
Valves and Check Valve.
On the outside, the relay box containing a motor relay and
a valve relay is installed.
Solenoid Valves: Reduces or holds the caliper fluid
pressure for each front disc brake or both rear disc brakes
according to the signal sent from the EHCU.
Reservoir: Temporarily holds the brake fluid that returns
from the front and rear disc brake caliper so that pressure
of front disc brake caliper can be reduced smoothly.
Plunger Pump: Feeds the brake fluid held in the reservoir
to the master cylinder.
Motor: Drives the pump according to the signal from
EHCU.
Check Valve: Controls the brake fluid flow.
ABS Warning Light
821RW033Vehicles equipped with the Anti-lock Brake System have
an amber ªABSº warning light in the instrument panel.
The ªABSº warning light will illuminate if a malfunction in
the Anti-lock Brake System is detected by the Electronic
Hydraulic Control Unit (EHCU). In case of an electronic
malfunction, the EHCU will turn ªONº the ªABSº warning
light and disable the Anti-lock braking function.
The ªABSº light will turn ªONº for approximately three
seconds after the ignition switch is to the ªONº position.
If the ªABSº light stays ªONº after the ignition switch is the
ªONº position, or comes ªONº and stays ªONº while
driving, the Anti-lock Brake System should be inspected
for a malfunction according to the diagnosis procedure.
Wheel Speed Sensor
It consists of a sensor and a rotor. The sensor is attached
to the knuckle on the front wheels and to the axle shaft
bearing holder on the rear wheels.
The rotor is press-fit in the axle shaft.The flux generated from electrodes magnetized by a
magnet in the sensor varies due to rotation of the rotor,
and the electromagnetic induction generates alternating
voltage in the coil. This voltage draws a ªsine curveº with
the frequency proportional to rotor speed and it allows
detection of wheel speed.
G-Sensor
The G-sensor installed inside the center console detects
the vehicle deceleration speed and sends a signal to the
EHCU. In 4WD operation, all four wheels may be
decelerated in almost the same phase, since all wheels
are connected mechanically.
This tendency is noticeable particularly on roads with low
friction coefficient, and the ABS control is adversely
affected.
The G-sensor judges whether the friction coefficient of
road surface is low or high, and changes the EHCU's
operating system to ensure ABS control.
Normal and Anti-lock Braking
Under normal driving conditions, the Anti-lock Brake
System functions the same as a standard power assisted
brake system. However, with the detection of wheel
lock-up, a slight bump or kick-back will be felt in the brake
pedal. This pedal ªbumpº will be followed by a series of
short pedal pulsations which occurs in rapid succession.
The brake pedal pulsation will continue until there is no
longer a need for the anti-lock function or until the vehicle
is stopped. A slight ticking or popping noise may be heard
during brake applications when the Anti-lock features is
being used.
When the Anti-lock feature is being used, the brake pedal
may rise even as the brakes are being applied. This is
also normal. Maintaining a constant force on the pedal
will provide the shortest stopping distance.
Brake Pedal Travel
Vehicles equipped with the Anti-lock Brake System may
be stopped by applying normal force to the brake pedal.
Although there is no need to push the pedal beyond the
point where it stops or holds the vehicle, by applying more
force the pedal will continue to travel toward the floor.
This extra brake pedal travel is normal.
Acronyms and Abbreviations
Several acronyms and abbreviations are commonly used
throughout this section:
ABS
Anti-lock Brake System
CKT
Circuit
DLC
Data Link Connector
EHCU
Electronic Hydraulic Control Unit
FL
Front Left
Page 815 of 3573
5A±5 BRAKE CONTROL SYSTEM
FR
Front Right
GEN
Generator
MV
Millivolts
RL
Rear Left
RR
Rear RightRPS
Revolution per Second
VDC
Volts DC
VA C
Volts AC
W/L
Warning Light
WSS
Wheel Speed Sensor
General Diagnosis
General Information
ABS malfunction can be classified into two types, those
which can be detected by the ABS warning light and those
which can be detected as a vehicle abnormality by the
driver.
In either case, locate the fault in accordance with the
ªBASIC DIAGNOSTIC FLOWCHARTº and repair.
Please refer to Section 5C for the diagnosis of
mechanical troubles such as brake noise, brake judder
(brake pedal or vehicle vibration felt when braking),
uneven braking, and parking brake trouble.
ABS Service Precautions
Required Tools and Items:
Box Wrench
Brake Fluid
Special Tool
Some diagnosis procedures in this section require the
installation of a special tool.
J-39200 High Impedance Multimeter
When circuit measurements are requested, use a circuit
tester with high impedance.
Computer System Service Precautions
The Anti-lock Brake System interfaces directly with the
Electronic Hydraulic Control Unit (EHCU) which is a
control computer that is similar in some regards to the
Powertrain Control Module. These modules are designed
to withstand normal current draws associated with
vehicle operation. However, care must be taken to avoid
overloading any of the EHCU circuits. In testing for opens
or shorts, do not ground or apply voltage to any of the
circuits unless instructed to do so by the appropriate
diagnostic procedure. These circuits should only be
tested with a high impedance multimeter (J-39200) or
special tools as described in this section. Power should
never be removed or applied to any control module with
the ignition in the ªONº position.
Before removing or connecting battery cables, fuses or
connectors, always turn the ignition switch to the ªOFFº
position.
General Service Precautions
The following are general precautions which should be
observed when servicing and diagnosing the Anti-lock
Brake System and/or other vehicle systems. Failure toobserve these precautions may result in Anti-lock Brake
System damage.
If welding work is to be performed on the vehicle using
an electric arc welder, the EHCU and valve block
connectors should be disconnected before the
welding operation begins.
The EHCU and valve block connectors should never
be connected or disconnected with the ignition ªONº .
EHCU of the Anti-lock Brake System are not
separately serviceable and must be replaced as
assemblies. Do not disassemble any component
which is designated as non-serviceable in this
Section.
If only rear wheels are rotated using jacks or drum
tester, the system will diagnose a speed sensor
malfunction and the ªABSº warning light will
illuminate. But actually no trouble exists. After
inspection stop the engine once and re-start it, then
make sure that the ªABSº warning light does not
illuminate.
If the battery has been discharged
The engine may stall if the battery has been completely
discharged and the engine is started via jumper cables.
This is because the Anti-lock Brake System (ABS)
requires a large quantity of electricity. In this case, wait
until the battery is recharged, or set the ABS to a
non-operative state by removing the fuse for the ABS
(40A). After the battery has been recharged, stop the
engine and install the ABS fuse. Start the engine again,
and confirm that the ABS warning light does not light.
Note on Intermittents
As with virtually any electronic system, it is difficult to
identify an intermittent failure. In such a case duplicating
the system malfunction during a test drive or a good
description of vehicle behavior from the customer may be
helpful in locating a ªmost likelyº failed component or
circuit. The symptom diagnosis chart may also be useful
in isolating the failure. Most intermittent problems are
caused by faulty electrical connections or wiring. When
an intermittent failure is encountered, check suspect
circuits for:
Suspected harness damage.
Poor mating of connector halves or terminals not fully
seated in the connector body (backed out).
Improperly formed or damaged terminals.