YH4
GRAND
VITARA
7B1-4 AUTOMATIC TRANSMISSION (4 A / T)
ItemSpecifications
Torque
conver-
terType
Stall torque ratio3-element, 1-step, 2-phase type (with TCC (lock-up)
mechanism)
2.4 (G16 engine) 2.0 (J20 engine) 1.9 (H25 engine)
Oil
pumpType
Drive systemTrochoid type oil pump
Engine driven
TypeForward 4-step, reverse 1-step planetary gear type
Shift position
ªPº range Gear in neutral, output shaft fixed,engine start
ªRº range Reverse
ªNº range Gear in neutral, engine start
ªDº range Forward 1st 2nd 3rd 4th (O / D)
(O / D ON) automatic gear change
ªDº range Forward 1st 2nd 3rd
(O / D OFF) automatic gear change
ª2º range (Normal mode) Forward 1st 2nd 3rd automatic gear
change
(Power mode) Forward 2nd 3rd automatic gear
change and fixed at 2nd gear
ªLº range Forward 1st 2nd 3rd reduction, and fixed at 1st gear
GearEngine typeG16 engineJ20 / H25 engines
change
device1st (low gear)2.8262.826device2nd (second gear)1.4931.493
Gear3rd (top gear)1.0001.000Gear
ratio4th (overdrive
4th gear)0.7300.689
Reverse (reverse
Reverse gear)2.7032.703
Control elements
Wet type multi-disc clutch 3 sets. . . . . . . . . .
Wet type multi-disc brake 4 sets. . . . . . . . . .
One-way clutch 3 sets. . . . . . . . . . . . . . . . . . .
TransferHi: 1.000 Lo: 1.816 (4WD model only)
Final gear reduction
ratio (Differential)5.125 (G16 engine) 4.875 (J20 / H25 engines)
Lubrica-
tionLubrication systemForce feed system by oil pump
CoolingCooling systemRadiator assisted cooling (water-cooled)
Fluid usedAn equivalent of DEXRONIII
YH4
GRAND
VITARA
Engine
Vehicle speed
sensor
Throttle position
sensor
ECT sensor
Cruise control
module
(if equipped)Torque converter Planetary gear
Final gear
reduction unit
Oil pump
Shift and TCC
solenoid valvesClutch and brake
Control valve
ªO / D OFFº lamp
ªPOWERº lamp
MILTransmission range
switch
O / D cut switch
P / N change switch
Transfer 4L switch
(if equipped)
CMP sensor Powertrain (engine) control module
Power transmission
Fluid pressure circuit
Electric signalInput speed sensor Brake pedal switch
Output speed sensor
AUTOMATIC TRANSMISSION (4 A / T) 7B1-7
ELECTRONIC SHIFT CONTROL SYSTEM
The gear ratio change in ªDº or ª2º range and torque converter clutch operation are controlled by Powertrain (En-
gine) Control Module.
YH4
GRAND
VITARA
7B1-26 AUTOMATIC TRANSMISSION (4 A / T)
Operation
VISUAL INSPECTION
Visually check following parts and systems.
INSPECTION ITEM
REFERRING SECTION
A / T fluid ± ± ± ± ± level, leakage, color
A / T fluid hoses ± ± ± ± ± disconnection, looseness, deterioration
Throttle (accelerator) cable ± ± ± ± ± play, installation
A / T throttle cable ± ± ± ± ± play, installation
A / T select cable ± ± ± ± ± installation, operation
Engine oil ± ± ± ± ± level, leakage
Engine coolant ± ± ± ± ± level, leakage
Battery ± ± ± ± ± fluid level, corrosion of terminal
Connectors of electric wire harness ± ± ± ± ± disconnection, friction
Fuses ± ± ± ± ± burning
Parts ± ± ± ± ± installation, damage
Bolt ± ± ± ± ± looseness
Other parts that can be checked visually
Also check following items at engine start, if possible.
ªO / D OFFº lamp
ªPOWERº lamp
Malfunction indicator lamp
Charge warning lamp
Engine oil pressure warning lamp
Engine coolant temp. meter
Other parts that can be checked visually
Section 0B
Section 7B1
Section 6E1 / 6E2
Section 7B1
Section 7B1
Section 0B
Section 0B
Section 6 / 6-1 / 7B1
Section 8
Section 7B1
Section 7B1
Section 6 / 6-1
Section 6H
Section 8 (Section 6A1 / 6A2 /
6A4 for pressure check)
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
AUTOMATIC TRANSMISSION (4 A / T) 7B1-29
Gear shift Transmission fluid Running condition
ConditionPossible CauseCorrection
Poor 3±4 shift, ex-3±4 shift valve stickingReplace.
cessive slippageShift solenoid valve-B stickingReplace.
Excessive shock onRegulator valve stickingReplace.
1±2 shiftFaulty accumulator, second brake pistonReplace.
Excessive shock onRegulator valve stickingReplace.
2±3 shiftFaulty accumulator, direct clutch pistonReplace.
Excessive shock on
3±4 shiftRegulator valve stickingReplace.
Non operate lock-TCC (Lock-up) control valve stickingReplace.
up systemSolenoid valve No.2 (TCC solenoid valve)
stickingReplace.
TROUBLE DIAGNOSIS TABLE 3
ConditionPossible CauseCorrection
Low fluid pressureLeakage from oil pressure circuitOverhaul.
Unable to run in all
rangeWear in oil pumpReplace.
Seizure in oil pumpReplace.
Fluid pressure leakage to over drive clutch
due to wear of oil pump bushingReplace.
Faulty in torque converterReplace.
YH4
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VITARA
7B1-30 AUTOMATIC TRANSMISSION (4 A / T)
Running condition Gear shift Abnormal
noise
ConditionPossible CauseCorrection
Poor 1st speed run-
ning or excessive
slippage in ªDº or ª2ºFluid pressure leakage from forward clutch
due to wear or breakage of O/D case seal
ringReplace.
Overdrive clutch slippingReplace.
Unable to run or ex-
cessive slippage in
ªLº rangeFluid pressure leakage of forward clutch
due to wear or breakage of O/D case seal
ringReplace.
Reverse brake disc slippingReplace.
Broken brake piston O-ringReplace.
Unable to run or ex-
cessive slippage in
ªRº rangeFluid pressure leakage to direct clutch due
to wear or breakage of center support seal
ringReplace.
Worn direct clutchReplace.
Poor 1±2 shift, ex-
cessive slippageFluid pressure leakage to overdrive clutch
due to wear or breakage of O/D case seal
ringReplace.
Faulty second brakeReplace.
Broken O-ring of second brake pistonReplace.
Faulty second coast brake (in ª2º range)Replace.
Poor 2±3 shift, ex-
cessive slippageFluid pressure leakage to overdrive clutch
due to wear or breakage of O/D case seal
ringReplace.
Worn direct clutch bushingReplace.
Direct clutch slippingReplace.
Foreign material caught in direct clutch pis-
ton check ballReplace.
Poor start or surging
in ªDº rangeFluid pressure leakage of forward clutch
due to wear or breakage of O/D case seal
ringReplace.
Malfunction of forward clutchReplace.
Poor 3±4 shift, ex-
ili
Faulty overdrive brakeReplace.
cessive slippageFaulty overdrive clutchReplace.
Poor start or judder-
ing in ªRº rangeFluid pressure leakage of direct clutch due
to wear or breakage of oil center support
seal ringReplace.
Worn direct clutchReplace.
Excessive shock on
1± 2 shiftFaulty one-way clutchReplace.
Non operate lock-up
systemFaulty torque converterReplace.
Abnormal noise in
ªPº or ªNº rangeWorn oil pumpReplace.
SCAN TOOL DATA-Refer to SECTION 6 / 6-1.
INSPECTION OF PCM AND ITS CIRCUIT-Refer to SECTION 6 / 6-1.
WIRE HARNESS AND CONNECTORS-Refer to SECTION 6 / 6-1.
YH4
GRAND
VITARA
7B1-46 AUTOMATIC TRANSMISSION (4 A / T)
DTC P0741 TCC (LOCK-UP) SOLENOID VALVE PERFORMANCE OR STUCK OFF
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
While running in 2nd or 4th gear, D range, TCC control
of PCM does not agree with actual operation of trans-
mission TCC even though solenoid valve is electrically
in good condition.
(2 driving cycles detection logic)TCC (lock-up) solenoid valve stuck
TCC control valve stuck
Valve body fluid passage clogged
TCC faulty
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 and check fuel level meter
indication is 1/4 or more.
3) Start engine, warm it up to normal operating temperature and shift transfer lever to ª2Hº or ª4Hº range.
4) Increase vehicle speed with D range, and check that gear position changes from 1st to 2nd and keep driving
about 20 mph, 30 km/h in 2nd of ªDº range for 10 seconds. (Throttle valve should be not at idle position and
the opening should be kept constant in this step.)
5) Keep driving about 50 mph, 80 km/h in 4th of ªDº range for 10 seconds.
6) Release accelerator pedal, decrease vehicle speed and stop vehicle.
7) Check pending DTC and DTC by using scan tool.
TROUBLESHOOTING
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2TCC solenoid valve operation check:
1) Check TCC solenoid valve operation referring to
ªSolenoid Valves Operation Checkº in this section.
Is it in good condition?Go to Step 3.Faulty TCC solenoid
valve.
3Valve body check:
1) Check valve body referring to ªUnit Repairº in this
section.
Is it in good condition?Faulty torque
converter.Faulty valve body.
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-49
DTC P0751 SHIFT SOLENOID VALVE-A (#1) PERFORMANCE OR STUCK OFF
DTC P0756 SHIFT SOLENOID VALVE-B (#2) PERFORMANCE OR STUCK OFF
DTC DETECTING CONDITION AND TROUBLE AREA
DTC DETECTING CONDITIONTROUBLE AREA
While running in D range, gear change control from
PCM to A / T does not agree with actual A / T gear posi-
tion even though solenoid valve is electrically in good
condition.
(A / T gear position is calculated based on engine
speed signal and vehicle speed sensor signal.)
(2 driving cycles detection logic)DTC P0751:
Shift solenoid valve-A stuck or leakage.
2-3 shift valve stuck.
Valve body fluid passage clogged.
Mechanical malfunction in transmission.
(Direct clutch malfunction)
DTC P0756:
Shift solenoid valve-B stuck or leakage.
1-2 shift valve stuck.
3-4 shift valve stuck.
Valve body fluid passage clogged.
Mechanical malfunction in transmission.
(2nd brake malfunction)
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 and check fuel level meter
indication is 1 / 4 or more.
3) Start engine, warm it up to normal operating temperature and shift transfer lever to ª2Hº or ª4Hº range.
4) Increase vehicle speed with D range, and check that gear position changes from 1st to 2nd, 3rd and 4th in that
order as vehicle speed increases, referring to ªGear Shift Diagramº in this section.
5) Stop vehicle and check pending DTC and DTC by using scan tool.
TROUBLESHOOTING
STEPACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2Shift solenoid valve-A or -B operation check:
1) Check shift solenoid valve-A or -B for operation
referring to ªSolenoid Valves Operation Checkº
section.
Is it in good condition?Go to Step 3.Faulty shift solenoid
valve-A or -B.
3Valve body check:
1) Check valve body and its passage referring to
ªUnit Repairº section.
Are they in good condition?Overhaul and repair
automatic transmis-
sion.Faulty valve body.