7b1 SUZUKI GRAND VITARA 2000 2.G Service Owner's Guide

YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-27
A / T BASIC CHECK
This inspection is important for troubleshooting when PCM (ECM) has detected no DTC and no abnormality has
been noted in visual inspection.
Follow flow table carefully.
STEP
ACTIONYESNO
1Was ªA / T DIAG. FLOW TABLEº performed?Go to Step 2.Go to ªA / T DIAG.
FLOW TABLEº.
2Perform MANUAL ROAD TEST in this section.
Is it OK?Go to Step 3.Go to Step 4.
3Proceed to TROUBLE DIAGNOSIS TABLE 1 in this
section.
Is trouble identified?Repair or replace
defective parts.Go to Step 5.
4Perform stall test, time rag test, line pressure test,
engine brake test and ªPº range test referring to STALL
TEST, LINE PRESSURE TEST, ENGINE BRAKE
TEST and ªPº RANGE TEST in this section.
Are the test results satisfactory?Go to Step 5.Proceed to
TROUBLE DIAGNO-
SIS TABLE 3 in this
section.
5Proceed to TROUBLE DIAGNOSIS TABLE 2 in this
section.
Is trouble identified?Repair or replace
defective parts.Proceed to
TROUBLE DIAGNO-
SIS TABLE 3 in this
section.

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 operate
Brake 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 4th
O / 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 pressure
Clogged oil pump strainer

Malfunction of pressure regulator valveWash strainer.
Overhaul valve body.
High fluid pressure
Pressure regulator valveOverhaul valve body.
Unable to run in all
range
Regulator 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
ª2º
Faulty 1±2 shift valveReplace.
Poor 1±2 shift, ex-
ili

Regulator valve stickingReplace.
cessive slippage
1±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 slippage
Shift solenoid valve-A stickingReplace.
Poor start or surg-
ing in ªDº range
Regulator 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 slippage
Shift solenoid valve-B stickingReplace.
Excessive shock on
Regulator valve stickingReplace.
1±2 shift
Faulty accumulator, second brake pistonReplace.
Excessive shock on
Regulator valve stickingReplace.
2±3 shift
Faulty accumulator, direct clutch pistonReplace.
Excessive shock on
3±4 shift
Regulator valve stickingReplace.
Non operate lock-
TCC (Lock-up) control valve stickingReplace.
up system
Solenoid valve No.2 (TCC solenoid valve)
stickingReplace.
TROUBLE DIAGNOSIS TABLE 3
ConditionPossible CauseCorrection
Low fluid pressure
Leakage from oil pressure circuitOverhaul.
Unable to run in all
range
Wear 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
GRAND
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 ª2º
Fluid 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 range
Fluid 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 range
Fluid pressure leakage to direct clutch due
to wear or breakage of center support seal
ringReplace.

Worn direct clutchReplace.
Poor 1±2 shift, ex-
cessive slippage
Fluid 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 slippage
Fluid 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 range
Fluid 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 slippage
Faulty overdrive clutchReplace.
Poor start or judder-
ing in ªRº range
Fluid pressure leakage of direct clutch due
to wear or breakage of oil center support
seal ringReplace.

Worn direct clutchReplace.
Excessive shock on
1± 2 shift
Faulty one-way clutchReplace.
Non operate lock-up
system
Faulty torque converterReplace.
Abnormal noise in
ªPº or ªNº range
Worn 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
AUTOMATIC TRANSMISSION (4 A / T) 7B1-31
Brake pedal Released Depressed
Voltage 0 VBattery
voltage
DIAGNOSTIC FLOW TABLE A-1 (NO TCC LOCK-UP OCCURS)
SYSTEM DESCRIPTION
PCM turns TCC solenoid OFF under any of the following conditions.

Brake pedal switch: ON

4WD LOW switch: ON

Cruise control module: TCC 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
C51-1-8 (G16 / J20 engines) or C51-1-2 (H25
engine) terminal of PCM coupler and ground.

Normal mode in ªDº range.

Transfer ª2Hº position.

Cruise control is not operated (if equipped).

Brake pedal released.

Drive vehicle with TCC ON condition
referring to ªTCC lock-up diagramº in
this section.
Is it battery voltage?Faulty TCC solenoid
valve, its circuit or
transmission.Go to Step 4.
4Is vehicle equipped with H25 engine?Go to Step 5.Go to Step 6.
5Brake switch signal inspection:
(1) With ignition switch ON, check voltage
between E61-31 terminal of PCM coupler
terminal and ground.
Is the result as specified?Go to Step 6.Faulty brake pedal switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.

YH4
GRAND
VITARA
7B1-32 AUTOMATIC TRANSMISSION (4 A / T)
Transfer gear
positionª4Lº or ªNº ª4Hº or ª2Hº
Voltage 0 VBattery
voltage
STEPACTIONYESNO
6ª4WD LOWº 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 7.Faulty ª4WD LOWº
switch or its circuit.
If OK, substitute a known-
good PCM and recheck.
7Is vehicle equipped with cruise control
system?Go to Step 8.Substitute a known-good
PCM and recheck.
8Cruise 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.

YH4
GRAND
VITARA
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.

YH4
GRAND
VITARA
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.

YH4
GRAND
VITARA
G16 / J20 Engines
H25 Engine
1. PCM
2. J / B
3. O / D cut switch
4. P / N change switch
5. J / C
1. PCM
2. Fuse
3. O / D cut switch
4. P / N change switch
5. J / C
6. J / C
AUTOMATIC TRANSMISSION (4 A / T) 7B1-35
DIAGNOSTIC FLOW TABLE B-1 ªO / D OFFº LIGHT CIRCUIT CHECK
(ªO / D OFFº LIGHT DOESN'T LIGHT AT IGNITION SWITCH ON BUT
ENGINE STARTS UP)
WIRING DIAGRAM
TROUBLESHOOTING
STEPACTIONYESNO
1ªO / D OFFº light circuit check:
(1) With ignition switch OFF, disconnect
couplers from PCM.
(2) Using service wire, connect E61-20
(G16 / J20 engines) or E61-7 (H25 engine)
terminal of disconnected PCM coupler and
ground.
Does ªO / D OFFº light turn ON at ignition
switch ON?Poor E61-20 (G16 / J20
engines) or E61-7 (H25
engine) terminal
connection.
If OK, substitute a known-
good PCM and recheck.Bulb burned out or faulty
ªW / Bº, ªB / Wº wire.

YH4
GRAND
VITARA
7B1-36 AUTOMATIC TRANSMISSION (4 A / T)
Switch ON
positionSwitch OFF
positionSwitch ON
position
Switch OFF
position
DIAGNOSTIC FLOW TABLE B-2 ªO / D OFFº LIGHT CIRCUIT CHECK
(ªO / D OFFº LIGHT COMES ON STEADILY)
WIRING DIAGRAM ± Refer to Table B-1 in this section.
TROUBLESHOOTING
STEPACTIONYESNO
1Check O / D cut Switch Position.
Is O / D cut switch turned OFF (Is switch button at OFF
position)?Go to Step 2.Turn O / D cut switch
OFF.
2Check Lamp Circuit for Short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Turn ignition switch ON.
Does ªO / D OFFº lamp come ON steadily?ªW / Bº circuit shorted
to ground.Go to Step 3.
3Check O / D cut Switch Circuit.
1) Check resistance between terminal E61-33
(G16 / J20 engines) or E61-14 (H25 engine) of
disconnected PCM connector and body ground with
O / D cut switch OFF.
Is continuity indicated?Go to Step 4.Check PCM ground
circuit for open.
If ground circuit is
OK, substitute a
known-good PCM
and recheck.
4Check O / D cut Switch for Operation.
1) Remove console box.
2) Disconnect O / D cut switch connector.
3) Check continuity between switch terminals under
each condition below.
Switch OFF position: No continuity
Switch ON position: Continuity
Is check result satisfactory?ªY / Rº circuit shorted
to ground.Replace O / D cut
switch.
Fig. for Step 1. Fig. for Step 4.