YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-9
1-1. CUSTOMER COMPLAINT ANALYSIS
Record details of the problem (failure, complaint) and how it occurred as described by the customer.
For this purpose, use of such a questionnaire form as shown below will facilitate collecting information to the
point required for proper analysis and diagnosis.
CUSTOMER QUESTIONNAIRE (EXAMPLE)
Customer's name:Model:VIN:
Date of issue:Date Reg.Date of problem:Mileage:
Problem Symptoms
ªABSº warning light abnormal: fails to turn on/fails to go off /
flashes
Abnormal noise while vehicle is running: from motor, from valve,
other__________________
Wheel is locked at braking:
Pump motor does not stop (running):
Braking does not work:
Other:
Frequency of occurrenceContinuous/Intermittent ( times a day, a month) /
other______________
Conditions for Occurrence
of Problem
Vehicle at stop & ignition switch ON:
When starting: at initial start only / at every start / Other______________
Vehicle speed: while accelerating / while decelerating / at stop /
while turning / while running at constant speed /
other________________
Road surface condition: Paved road / rough road / snow-covered
road / other_________________
Chain equipment:
Environmental ConditionWeather: fair / cloudy / rain / snow / other___________________
Temperature: F (C)
Diagnostic Trouble Code
First check: Normal code/malfunction code ( )
Second check after
test drive: Normal code / malfunction code ( )
YH4
GRAND
VITARA
5E1-16 ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL)
-1. Main fuse
-2. Ignition switch
-3. Circuit fuse for IG
-4. ªABSº warning lamp
-5. ABS hydraulic unit / control
module assembly
5-1. Fail-safe relay
5-2. To solenoid valves and
pump motor relay
(ABS hydraulic unit)
-6. Diagnosis connector
(Black connector)
6-1. Diag. switch terminal
6-2. Diag. ground terminal
-7. Combination meter
7-1. ABS lamp driver module
-8. ABS hydraulic unit/
control module connector
of harness
-9. EBD warning lamp
(Brake warning lamp)
-10. Parking brake switch
-11. Brake fluid level switch
TABLE ± A ªABSº WARNING LAMP CIRCUIT CHECK ± LAMP DOES NOT
COME ªONº AT IGNITION SWITCH ON
CIRCUIT DESCRIPTION
Operation (ON / OFF) of the ªABSº warning lamp is controlled by the ABS control module and ABS lamp driver mod-
ule.
If the Antilock brake system is in good condition, the ABS control module turns the ªABSº warning lamp ON at the
ignition switch ON, keeps it ON for 2 seconds only and then turns it OFF. If an abnormality in the system is detected,
the lamp is turned ON by ABS control module. Also, it is turned ON by ABS lamp driver module when the connector
of the ABS control module was disconnected.
INSPECTION
STEPACTIONYESNO
11) Turn ignition switch ON.
Do other warning lamp come ON?Go to step 2.Go to step 4.
21) Disconnect ABS hydraulic unit / control module
connector.
Does ABS warning lamp light with ignition switch ON?Replace ABS
hydraulic unit / control
module assembly.Go to step 3.
31) Remove combination meter.
Is bulb of ABS warning lamp in good condition?ªBl / Oº circuit shorted
to ground. If OK,
replace ABS
warning circuit (lamp
driver module).Replace bulb.
4Is IG fuse in good condition?Open in ªB / Wº wire to
combination meter or
poor connection.Repair and
replace.
YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-27
1. ABS hydraulic unit/
control module assembly
2. ABS hydraulic unit/
control module
connector
1. ABS hydraulic
unit / control
module connector
DTC 57 (DTC C1057) ± SOLENOID AND PUMP MOTOR POWER SOURCE
CIRCUIT
DESCRIPTION
The ABS control module monitors the voltage at terminal ( ªA11º and ªA27º) of the fail-safe and pump motor relays
circuit constantly with the ignition switch turned ON. When all solenoid circuit voltages are below the specified value
or the voltage at the terminal ªA27º became below the specified value while the pump motor is operating, this DTC
will be set. As soon as the voltage rises to the specified level, the set DTC will be cleared.
INSPECTION
STEPACTIONYESNO
1Check battery voltage. Is it about 11 V or higher?Go to step 2.Check charging
system referring
to ªCHARGING
SYSTEMº section.
2Check ABS main fuse and connection. Is it in good
condition?Go to step 3.Repair and / or
replace fuse.
31) Ignition switch OFF.
2) Disconnect ABS hydraulic unit / control module
connector. (See Fig. 1)
3) Check proper connection to ABS hydraulic unit /
control module connector at terminal ªA27º.
4) If OK, then measure voltage between connector
terminal ªA27º and body ground.
Is it 10 ± 14 V?Substitute a
known-good
ABS hydraulic
unit / control
module assembly
and recheck.ªW / Blº circuit open.
Fig. 1
YH4
GRAND
VITARA
7B1-28 AUTOMATIC TRANSMISSION (4 A / T)
Transmission fluid Running condition Running condition Gear shift
TROUBLE DIAGNOSIS TABLE 1
ConditionPossible CauseCorrection
TCC does not operateBrake pedal (stop lamp) switch or its
circuit faulty (H25 engine only)
4WD low switch or its circuit faulty
Engine coolant temp. sensor or its
circuit faulty
Cruise control signal circuit faulty
(if equipped)DIAGNOSTIC FLOW TABLE A-1
Gear does not change
to 4thO / D cut switch or its circuit faulty
4WD low switch or its circuit faulty
Engine coolant temp. sensor or its
circuit faulty
Cruise control signal circuit faulty
(if equipped)DIAGNOSTIC FLOW TABLE A-2
TROUBLE DIAGNOSIS TABLE 2
ConditionPossible CauseCorrection
Low fluid pressureClogged oil pump strainer
Malfunction of pressure regulator valveWash strainer.
Overhaul valve body.
High fluid pressurePressure regulator valveOverhaul valve body.
Unable to run in all
rangeRegulator valve stickReplace.
Clogged oil strainerWash strainer.
Seized or broken planetary gearRepair or replace.
Faulty manual valveReplace.
Poor 1st speed run-
ning or excessive
slippage in ªDº or
ª2ºFaulty 1±2 shift valveReplace.
Poor 1±2 shift, ex-
ili
Regulator valve stickingReplace.
cessive slippage1±2 shift valve stickingReplace.
Shift solenoid valve-B stickingReplace.
Intermediate coast modulator valve stick-
ingReplace.
Poor 2±3 shift, ex-
ili
2±3 shift valve stickingReplace.
cessive slippageShift solenoid valve-A stickingReplace.
Poor start or surg-
ing in ªDº rangeRegulator valve stickingReplace.
YH4
GRAND
VITARA
7E
DIFFERENTIAL (FRONT) 7E-1
The differential assembly using a hypoid bevel pinion
and gear is installed to the front axle.
4WD control system controls drive force to be trans-
mitted to front axles or not. The reduction ratio varies
depending on transmission or engine type.The differential assembly is decisive in that the drive
power is concentrated there. Therefore, use of genu-
ine parts and specified torque is compulsory. Further,
because of sliding tooth meshing with high pressure
between bevel pinion and gear, it is mandatory to lu-
bricate them by hypoid gear oil.
SECTION 7E
DIFFERENTIAL (FRONT)
CONTENTS
GENERAL DESCRIPTION7E- 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4WD CONTROL SYSTEM7E- 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS7E- 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS TABLE7E- 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Assembly7E- 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4WD Control System Diagnostic Flow Table 7E- 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4WD CONTROL CIRCUIT INSPECTION 7E- 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE7E- 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE SERVICE7E- 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gear Oil Change7E- 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INSPECTION7E-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4WD Control System7E-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Actuator7E-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Pump Assembly7E-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVAL AND INSTALLATION 7E-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Mountings7E-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISMOUNTING7E-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOUNTING7E-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR7E-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TIGHTENING TORQUE SPECIFICATIONS7E-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REQUIRED SERVICE MATERIAL7E-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS7E-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION
YH4
GRAND
VITARA
1. 4WD switch
2. Transfer
3. Blank
4. Blank
5. ECM or PCM
6. Glove box7. Air pump assembly
8. Actuator
9. Axle lock clutch
10. Free axle hub
11. 4WD indicator lamp
7E-2 DIFFERENTIAL (FRONT)
4WD CONTROL SYSTEM
When the 4WD switch is turned ON by shifting the transfer shift lever, ECM (PCM) (G16 and J20 engine models)
or 4WD controller (H25 engine model) actuates (energizes) the air pump assembly. Then positive pressure is sent
from the air pump assembly to the actuator installed to the differential case and causes the axle lock clutch and
the free axle hub in the differential case to be engaged, resulting in the 4WD mode. Only when running in the 4WD
mode, front axles are joined to differential case, and they become free when 2WD mode is used (or when transfer
shift lever is shifted to N position), thereby reducing the power loss.
YH4
GRAND
VITARA
1. 4WD switch
2. Air pump assembly
3. Pump motor
4. Release valve
5. Pressure switch6. Transfer
7. Front differential
8. Air hose and pipe
9. 4WD indicator lamp
10. To ignition switch
11. ECM or PCM
Operation
(refer to ªComponents and Functionsº)
Power supply
(from ECM or PCM)
DIFFERENTIAL (FRONT) 7E-3
System Circuit and Operation
YH4
GRAND
VITARA
7E-4 DIFFERENTIAL (FRONT)
Components and Functions
ComponentFunction
4WD switch
When the transfer shift lever is shifted to 4L or 4H position, this switch turns ON
and causes the 4WD control system to turn ON, unless it is shifted to N or 2H
within 1 second.
ECM or PCM
When the 4WD switch turns ON [unless it turns OFF within 1 second], this com-
ponent actuates the pump assembly. If the pressure in the air pump assembly
fails to increase higher than the set level even after the pump motor has run more
than 10 seconds, this component stops the motor to protect it.
Air pump assembly
Pump motor
Release valve
Pressure switchThe air pump assembly consists of a pump motor, release valve and a pressure
switch.
Pump motor:
Produces positive pressure which actuates the actuator.
Release valve:
Closes when transfer shift lever is shifted to 4H or 4L so that the positive pressure
is applied to the actuator, and opens when N or 2H to release the pressure to the
atmosphere.
Pressure switch:
Turns ON and OFF depending on the pressure level in the pump assembly
(whether higher or lower than the set pressure level). ECM or PCM detects the
pressure level through this switch.
Differential case assembly
Free axle hub
Axle lock clutch
ActuatorThe free axle hub, axle lock clutch and actuator are installed in the differential
left case. The positive pressure produced in the air pump assembly is applied
to the actuator which then pushes the axle lock clutch to be engaged with the free
axle hub. In this state, the drive force is transmitted to the front axle, resulting in
the 4WD mode.
When the actuator is free from the positive pressure [when it is under the atmo-
spheric pressure], the axle lock clutch is pushed back by the return spring force
and cannot be engaged with the free axle hub, resulting in the 2WD mode.
ª4WDº indicator lampIt lights up when 4WD control system is in the 4WD mode.