Page 509 of 801
YH4
GRAND
VITARA
DIFFERENTIAL (FRONT) 7E-7
1
1. ECM (PCM); viewed from harness side
4WD CONTROL CIRCUIT INSPECTION
Voltage Check [G16 and J20 engine models]
Check for input or output voltage (voltage between each circuit and
body ground) of ECM (PCM) with ECM (PCM) connector con-
nected and ignition switch turned ON.
TER-
MINALCIRCUITWIRE
COLORNORMAL
VOLTAGECONDITION
E6110 ± 14 VTransfer shift lever: 2H or NE61-
194WD Indicator lampOr / B0 ± 1 V4 seconds after transfer shift lever shifted
to 4H or 4L
C51 2Air pump assembly0 ± 1 VTransfer shift lever: 2H or NC51-2
-7(Pump motor and release
valve)R10 ± 14 V1 seconds after transfer shift lever shifted
to 4H or 4L
C51-24WD switchB/Or10 ± 14 VTransfer shift lever: 2H or N
-184WD switchB/Or0 ± 1 VTransfer shift lever: 4H or 4L
C51-
3-17GroundB/Bl0 ± 1 V±
C51 2Airpumpassembly0 ± 1 VTransfer shift lever: 2H or NC51-2
-27
Air um assembly
(pressure switch)P10 ± 14 V4 seconds after transfer shift lever shifted
to 4H or 4L
Page 510 of 801
YH4
GRAND
VITARA
7E-8 DIFFERENTIAL (FRONT)
1. ECM (PCM); viewed from harness side
Voltage Check [H25 engine model]
TER-
MINALCIRCUITWIRE
COLORNORMAL
VOLTAGECONDITION
C51 110 ± 14 VTransfer shift lever: 2H or NC51-1
-74WD Indicator lampOr / B0 ± 1 V4 seconds after transfer shift lever shifted
to 4H or 4L
C51 1Air pump assembly0 ± 1 VTransfer shift lever: 2H or NC51-1
-15(Pump motor and release
valve)R10 ± 14 V1 seconds after transfer shift lever shifted
to 4H or 4L
C51-14WD switchB/Or10 ± 14 VTransfer shift lever: 2H or N
-114WD switchB/Or0 ± 1 VTransfer shift lever: 4H or 4L
C51-3
-26GroundB/Bl0 ± 1 V±
C51-1Airpumpassembly0 ± 1 VTransfer shift lever: 2H or NC51-1
-18
Air um assembly
(pressure switch)P10 ± 14 V4 seconds after transfer shift lever shifted
to 4H or 4L
Page 512 of 801

YH4
GRAND
VITARA
7E-10 DIFFERENTIAL (FRONT)
1. Plugged hose
2. Adjusting screw
3. Pipe (to air pump assembly)
4. Hose (to differential carrier)
5. Differential housing
4 5
INSPECTION
4WD Control System
1) Install special tool to air hose connecting between air pump as-
sembly and differential (actuator) as shown in figure. Tighten ad-
justing screw of special tool as far as it stops. Close air check
side opening by using fuel hose as blind plug.
Special Tool
(A): 09918-18110
(B): 09367-04002
NOTE:
Use care not to bend any part of hose.
2) Turn ON ignition switch and shift transfer lever from 2H to 4H
range.
3) Check that motor starts running (a sound can be heard) within
1 second and it stops when gauge of special tool indicates speci-
fied pressure value.
Check also for air leakage.
Pressure specification:
30.0 ± 45.0 kPa (0.30 ± 0.45 kg / cm
2, 4.25 ± 6.40 psi)
4) Check that pressure value indicated on gauge of special tool
drops as soon as transfer lever is shifted to 2H position.
5) Start motor by shifting transfer lever to 4H position again. Loos-
en adjusting screw to lower pressure value on gauge. Motor
should start to run again and stop in about 4 seconds.
6) With the adjusting screw of special tool loosened, shift transfer
shift lever to N or 2H position and then 4L or 4H position.
Pump motor should stop about 10 seconds after motor starts to
run.
Page 513 of 801

YH4
GRAND
VITARA
DIFFERENTIAL (FRONT) 7E-11
1. Differential housing
2. Adjusting screw
3. To air compressor
Actuator
1) Disconnect air hose from pump assembly and install special tool
to air hose as shown in figure. Loosen adjusting screw of special
tool.
Special Tool
(A): 09918-18110
2) Connect compressor air hose to special tool.
Blow air and turn adjusting screw to obtain specified pressure.
Specified pressure: 30.0 kPa (0.3 kg / cm
2, 4.25 psi)
CAUTION:
Do not apply a pressure exceeding 200 kPa (2.0 kg / cm
2,
28.4 psi) which may cause damage to diaphragm.
3) With the vehicle lifted so that both of the front wheels are off the
ground, turn one of the front wheels by hand and check the other
wheel, which should act as described below.
When the pressure from compressor is applied to actuator:
The other front wheel should turn in the direction opposite to
the wheel being turned by hand.
When the pressure from compressor is not applied to actuator:
The other front wheel should remain stationary while the wheel
pushed by hand is turning.
If the result is not satisfactory, inspect differential assembly. Re-
fer to ªINSPECTIONº of SECTION 7E in UNIT REPAIR MANU-
AL.
Page 514 of 801

YH4
GRAND
VITARA
7E-12 DIFFERENTIAL (FRONT)
1. Pump assembly
Air Pump Assembly
Removal / Installation
1) Disconnect air hoses and coupler from air pump assembly.
2) Remove pump assembly by removing bolts.
3) Reverse removal procedure for installation.
Tightening Torque
(a): 13 N
.m (1.3 kg-m, 9.5 lb-ft)
Inspection
1) Install special tool, voltmeter and battery to pump assembly as
shown in figure.
2) Tighten adjusting screw of special tool as far as it stops and
close its air check side opening by using fuel hose as blind plug.
Special Tool
(A): 09918-18110
3) Check that motor starts to run (a sound can be heard) when bat-
tery is connected and it stops when specified pressure is ob-
tained.
Check also for air leakage.
Specified pressure: 30.0 ± 45.0 kPa
(0.30 ± 0.45 kg / cm
2, 4.25 ± 6.40 psi)
4) Check that value indicated on voltmeter is within specification
shown below.
When motor is running: 0 ± 1 V
When motor has stopped running: 10 ± 14 V
CAUTION:
Do not run motor more than 10 seconds continuously to
prevent motor breakage.
Page 516 of 801
YH4
GRAND
VITARA
7E-14 DIFFERENTIAL (FRONT)
1. Mounting bracket R
2. Mounting bracket L
1. Bolt and nut
2. Differential carrier
3. Cross member
4. Bolt
5. Differential rear mounting assembly
7) Position each bush to bracket as shown.
Length ªaº: 3.0 mm (0.12 in.)
8) Use following torque for reinstallation.
Tightening Torque
(a): 85 N
.m (8.5 kg-m, 61.5 lb-ft)
(b): 50 N
.m (5.0 kg-m, 36.5 lb-ft)
REAR MOUNTING
(For front differential carrier)
1) Lift up vehicle and remove mounting assembly by removing 2
bolts and nuts from differential carrier side and 2 bolts from cross
member side.
2) Check mounting rubber for damage or deterioration and replace
as necessary.
3) Use following torque for reinstallation.
Tightening Torque
(a): 50 N
.m (5.0 kg-m, 36.5 lb-ft)
Page 517 of 801
YH4
GRAND
VITARA
DIFFERENTIAL (FRONT) 7E-15
A: Match marks
1. Mounting bracket bolt
2. Flange bolt and nut
1. Bolts
1. Mounting bracket bolt
2. Mounting bracket R
3. Differential housing
DISMOUNTING
1) Lift up vehicle and drain oil.
2) Disconnect air hose and breather hose from differential housing.
3) Before removing propeller shaft, give match marks on joint
flange and propeller shaft as shown.
4) Remove propeller shaft flange by removing its 4 bolts and sus-
pend it with cord or the like.
NOTE:
If pull out propeller shaft, transfer oil must be drained be-
fore pulling out.
5) Remove 3 bolts for left mounting bracket and 3 bolts for drive
shaft flange to set left side of differential free.
6) Remove 2 bolts from cross member to set differential rear
mounting free.
7) With differential housing assembly held with transmission jack,
remove mounting bolts on right end of housing.
Page 518 of 801
YH4
GRAND
VITARA
7E-16 DIFFERENTIAL (FRONT)
(a)
(a)
(a)
1. Drive shaft joint R
2. Differential housing3. Transmission jack
4. Screw driver
8) Using 2 large screwdrivers as levers, pull out right side drive
shaft joint from differential and dismount housing assembly from
vehicle.
CAUTION:
During above work, use care not to cause damage to
drive shaft boot.
REMOUNTING
For remounting, reverse dismounting procedure and use following
tightening torque.
Tightening Torque
(a): 50 N
.m (5.0 kg-m, 36.5 lb-ft)
After tightening all fasteners properly, fill hypoid gear oil as speci-
fied and check tightening of plugs with specification.