4wd switch SUZUKI GRAND VITARA 2000 2.G Service Owner's Manual

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AUTOMATIC TRANSMISSION (4 A / T) 7B1-33
O / D cut
switchOFF ON
VoltageBattery
voltage0 V
DIAGNOSTIC FLOW TABLE A-2 (NO GEAR SHIFT TO O / D)
SYSTEM DESCRIPTION
PCM does not shift to O / D gear under any of the following conditions.

O / D cut switch: ON

4WD LOW switch: ON

Cruise control module: O / D OFF command signal is output (if equipped).

ECT: ECT < 30C (86F)
TROUBLESHOOTING
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 person, a driver and tester, on a level road.
STEPACTIONYESNO
1Was ªAUTOMATIC TRANSMISSION
DIAGNOSTIC FLOW TABLEº performed?Go to Step 2.Go to ªAUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLEº.
2ECT check:
(1) Warm up engine to normal operating
temperature.
(2) Check ECT using scan tool.
Is ECT more than 30C (86F)?Go to Step 3.Faulty ECT sensor,
its circuit or engine
cooling system.
If OK, substitute a known-
good PCM and recheck.
3Perform running test under the following
conditions and check voltage between
C51-1-2 (G16 / J20 engines) or C51-1-6 (H25
engine) terminal of PCM coupler and ground,
C51-1-1 terminal of PCM coupler and ground.

O / D cut switch OFF (ªO / D OFFº lamp OFF).

Normal mode in ªDº range.

Transfer ª2Hº position.

Cruise control is not operated (if equipped).

Drive vehicle with 4th gear condition
referring to ªGear shift diagramº in this
section.
Is each voltage about 0 V?Faulty shift solenoid
valve, its circuit or
transmission.ªGº wire or ªG / Rº wire
shorted to power circuit.
If OK, go to Step 4.
4O / D cut switch signal inspection:
(1) With ignition switch ON, check voltage
between E61-33 (G16 / J20 engines) or
E61-14 (H25 engine) terminal of PCM
coupler and ground.
Is the result as specified?Go to Step 5.Faulty O / D cut switch or
its circuit.
If OK, substitute a known-
good PCM and recheck.

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7B1-34 AUTOMATIC TRANSMISSION (4 A / T)
Transfer gear
positionª4Lº or ªNº ª4Hº or ª2Hº
Voltage 0 VBattery
voltage
STEPACTIONYESNO
54WD LOW switch signal inspection:
(1) With ignition switch ON, check voltage
between C51-1-26 (G16 / J20 engines) or
C51-1-5 (H25 engine) terminal of PCM
coupler and ground.
Is the result as specified?Go to Step 6.Faulty 4WD LOW switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.
6Is vehicle equipped with cruise control
system?Go to Step 7.Substitute a known-good
PCM and recheck.
7Cruise control signal inspection:
(1) With ignition switch ON, check voltage
between E61-35 (G16 / J20 engines) or
E61-3 (H25 engine) terminal of PCM
coupler and ground.
Is it battery voltage?Substitute a known-good
PCM and recheck.Faulty cruise control
module or its circuit.
If OK, substitute a known-
good PCM and recheck.

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G16/J20 Engines H25 Engine
G16/J20 Engines
H25 Engine
1. PCM
2. A / T output speed sensor 23
22
WOr10 9
WOr
7B1-44 AUTOMATIC TRANSMISSION (4 A / T)
DTC P0720 (DTC NO.75) OUTPUT SPEED SENSOR CIRCUIT MALFUNCTION
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA

With 4WD LOW switch OFF, no output speed sensor
signal is inputted while vehicle speed sensor signal
are inputted.
or

With 4WD LOW switch OFF, no output speed sensor
signal is inputted while engine running at higher than
specified engine speed with ªDº range.
(2 driving cycles detection logic)
A / T output speed sensor or its circuit

PCM
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and be very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 persons, a driver and a tester, on a level road.
1) Connect scan tool to DLC with ignition switch OFF, if available.
2) Clear DTC.
3) Start engine and shift transfer lever to ª2Hº or ª4Hº range.
4) Drive vehicle at 40 km / h (25 mph) or more for longer than 10 sec. (or higher than 3500 rpm engine speed with
D range for longer than 10 sec.)
5) Stop vehicle and check DTC and / or pending DTC.

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G16 / J20 Engines
H25 Engine
1. PCM
2. 4WD low switch
3. J / C
7B1-52 AUTOMATIC TRANSMISSION (4 A / T)
DTC P1875 4WD LOW SWITCH CIRCUIT MALFUNCTION (if equipped)
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
While driving at higher than specified vehicle speed
and with more than specified throttle valve opening,
the following conditions are satisfied for specified time.

Vehicle speed sensed by vehicle speed sensor is
more than 10 km / h higher than that sensed by A / T
output speed sensor.
(2 driving cycles detection logic)
4WD LOW switch or its circuit

PCM
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and be very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 persons, a driver and a tester, on a level road.
1) Connect scan tool to DLC with ignition switch OFF.
2) Clear DTC, pending DTC and freeze frame data in PCM memory by using scan tool.
3) Start engine.
4) Increase vehicle speed to about 30 km/h (19 mph) or more in D range and is in 2H position.
5) Keep driving at above vehicle speed for 30 seconds.
6) Stop vehicle and shift transfer lever to 4L position with A/T selector lever is in P range
7) Increase vehicle speed to about 25 km/h (15 mph) or more in D range and is in 4L position.
8) Keep driving at above vehicle speed for 30 seconds.
9) Stop vehicle and check pending DTC and DTC by using scan tool.

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1
1. 4WD low switch
AUTOMATIC TRANSMISSION (4 A / T) 7B1-53
TROUBLESHOOTING (DTC P1875)
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
24WD low switch and its circuit check:
When using SUZUKI scan tool:
1) Connect SUZUKI scan tool to DLC with ignition
switch OFF.
2) Turn ignition switch ON.
3) Select ªData listº mode on scan tool.
4) Check 4WD low switch signal (ON or OFF) on
display when shifting transfer lever to each
position.
4H or 2H position : OFF
4L position : ON
Is OFF / ON displayed as described above?
When not using SUZUKI scan tool:
1) Remove PCM cover.
2) Turn ignition switch ON.
3) Check voltage at terminal C51-1-26 for G16 / J20
(C51-1-5 for H25) of PCM connector connected
when shifting transfer lever to each position.
4H or 2H position : 10 ± 14 V
4L position : 0 ± 1 V
Is voltage as specified?Check for poor con-
nection at the termi-
nal of PCM if voltme-
ter is used in Step 2.
If connection is OK,
intermittent trouble
or faulty PCM.
Check for intermittent
referring to ªIntermit-
tent and Poor
Connectionº in
Section 0A.Go to Step 3.
34WD low switch check:
1) Check 4WD low switch for operation referring to
ª4WD Low Switch Inspectionº below.
Is check result satisfactory?ªOr / Wº or ªBº circuit
open or short. If wires
and connections are
OK, substitute a
known-good PCM
and recheck.Replace 4WD low
switch.
4WD Low Switch Inspection
1) Disconnect negative cable at battery.
2) Disconnect 4WD low switch coupler.
3) Check continuity between 4WD low switch terminals.
There should be continuity when transfer lever shifted to 4L posi-
tion and should be infinity when transfer lever shifted to 4H or 2H
positions.
If not, replace 4WD low switch.
4) Connect 4WD low switch coupler and battery negative cable.

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1. Bolt
2. Transfer assembly
1. Bolt
2. Engine rear mounting3. Transfer assembly
1. Bolt
2. Transfer assembly
3. Transmission jack
7D-6 TRANSFER
IN CABIN
Remove gear shift lever case and then remove transfer center case
bolt.
ON LIFT
1) Remove transfer mounting (engine rear mounting) by removing
bolts.
2) Apply transmission jack to transfer to support it.
3) Remove couplers for 4WD / 4WD-LOW switches lead.
4) Remove transfer front case bolts.
5) With transfer assembly supported with transmission jack, slide
it rearward and when it is apart from transmission, lower it.
REMOUNTING
For remounting, reverse dismounting procedure described above,
noting following.

Be sure to use specified torque for tightening.

Clamp wiring and breather hose securely.

Clamp shift lever boot securely.

Fill specified gear oil by specified amount.

Connect battery and check for function.

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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.

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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

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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.

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DIFFERENTIAL (FRONT) 7E-5
DIAGNOSIS
DIAGNOSIS TABLE
Differential Assembly
ConditionPossible CauseCorrection
Gear noise
Deteriorated or water mixed lubricant

Inadequate or insufficient lubricant

Maladjusted backlash between bevel
pinion and gear

Improper tooth contact in the mesh between
bevel pinion and gear

Loose bevel gear securing bolts

Damaged side gear(s) or side pinion(s)Repair and replenish
Repair and replenish
Adjust
Adjust or replace
Replace or retighten
Replace
Bearing noise
(Constant noise) Deteriorated or water
mixed lubricant

(Constant noise) Inadequate or insufficient
lubricant

(Noise while coasting) Damaged bearing(s)
of bevel pinion

(Noise while turning) Damaged diff. side
bearing(s) or axle bearing(s)Repair and replenish
Repair and replenish
Replace
Replace
Oil leakage
Worn or damaged oil seal

Excessive oil

Loose differential carrier boltsReplace
Adjust oil level
Replace or retighten
2WD / 4WD
switching error
Defective actuator

Abnormality in 4WD control systemReplace
Inspect referring to ª4WD
CONTROL SYSTEM DIAG-
NOSTIC FLOW TABLEº.
4WD Control System Diagnostic Flow Table
Before performing the trouble diagnosis, check that the transfer and front differential are in good condition and
there is no air leakage from air hoses and the actuator. Refer to ªON-VEHICLE SERVICEº in this section for air
leakage.
[NOTES ON SYSTEM CIRCUIT INSPECTION]

Be sure to read ªPrecautions for Electrical Circuit Serviceº in Section 0A before circuit inspection and observe
what is written there.

For system circuit, refer to the figure of ªGENERAL DESCRIPTIONº in this section.

For terminal arrangement, refer to ª4WD Control Circuit Inspectionº in this section.