YH4
GRAND
VITARA
7B1-8 AUTOMATIC TRANSMISSION (4 A / T)
G16 / J20 Engines
1. PCM (ECM)
2. VSS
3. CMP sensor
4. TP sensor
5. ECT sensor
6. A / T input speed sensor
7. A / T output speed sensor
8. Transmission range switch9. Shift solenoid-A
10. Shift solenoid-B
11. TCC solenoid
12. Data link connector
13. Cruise control module
14. ªPOWERº lamp
15. ªO / D OFFº lamp
16. MIL17. O / D cut switch
18. P / N change switch
19. 4WD low switch
20. Main relay
21. Ignition switch
22. Battery
23. PCM (ECM) connector terminal
(viewed from harness side) Bl / Y
Bl / G
W
OrC51-1-11
C51-1-10
C51-1-23
C51-1-22
12V
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-9
H25 Engine
1. PCM (ECM)
2. VSS
3. CMP sensor
4. TP sensor
5. ECT sensor
6. Brake pedal switch
7. A / T input speed sensor
8. A / T output speed sensor9. Transmission range switch
10. Shift solenoid-A
11. Shift solenoid-B
12. TCC solenoid
13. Data link connector
14. Cruise control module
15. ªPOWERº lamp
16. ªO / D OFFº lamp17. MIL
18. O / D cut switch
19. P / N change switch
20. 4WD low switch
21. Main relay
22. Ignition switch
23. Battery
24. PCM (ECM) connector terminal
(viewed from harness side) Bl / Y
Bl / G
W
OrC51-1-16
C51-1-8
C51-1-10
C51-1-9
12V
YH4
GRAND
VITARA
7B1-10 AUTOMATIC TRANSMISSION (4 A / T)
Shift the select
lever with its
button pushed
in.
Shift the select
lever without
pushing its
button.
RANGE
GEAR
SOLENOIDS
Fail Safe Function
This function is provided by the safe mechanism that assures safe driveability even when the shift solenoid valve
or speed sensor fails.
The table below shows the gear position in each shift under a normal/abnormal condition.
Condition
Shift position
Normal
Shift solenoid
valve-A(#1)
abnormalShift solenoid
valve-B(#2)
abnormalShift solenoid
valves-A&B
(#1 and #2) abnormal
1st1st
D2nd3rdO/DD3rdO/DO/D
O/DO/D
1st1st
22nd3rd3rd3rd
(3rd)3rd
L1st1st1st1stL(2nd)(2nd)1st1st
Change Mechanism
The same select pattern shift lever is used as the floor type and fre-
quently used ªNº and ªDº ranges are made selectable freely.
Operation of Shift Solenoids and TCC Solenoid
D2LP, N & R
1st2nd3rd4th
(O / D)1st2nd1stÐ
Shift solenoid-A (#1, NO.1)
Shift solenoid-B (#2, NO.2)
TCC solenoid
: ON (valve is open): OFF (valve is closed)
YH4
GRAND
VITARA
7B1-24 AUTOMATIC TRANSMISSION (4 A / T)
MALFUNCTION INDICATOR LAMP (MIL) CHECK
Refer to the same item in Section 6 / 6-1 for checking procedure.
ªO / D OFFº LAMP CHECK
1) Check that O / D cut switch button is at OFF position (pushed).
2) Turn ignition switch ON.
3) Check that ªO / D OFFº lamp lights for about 2 ± 4 sec. and then goes OFF.
If anything faulty is found, advance ªDiagnostic flow table B-1 or B-2º O / D OFF ªLAMP CIRCUIT CHECKº.
ªPOWERº LAMP CHECK
1) Check that Power / Normal change switch button is at Normal position.
2) Turn ignition switch ON.
3) Check that ªPowerº Lamp light for 2 ± 4 sec. and then goes OFF.
If anything faulty is found, advance ªDiagnostic flow table B-3 or B-4 ªPOWERº LAMP CIRCUIT CHECK 2.
DIAGNOSTIC TROUBLE CODE (DTC) CHECK
Refer to the same item in Section 6 / 6-1 for checking procedure.
DIAGNOSTIC TROUBLE CODE (DTC) CLEARANCE
Refer to the same item in Section 6 / 6-1 for clearance procedure.
DIAGNOSTIC TROUBLE CODE (DTC) TABLE (A / T RELATED CODE)
DTC NO.MIL
Using
scan toolNot using
scan toolDETECTED ITEMDETECTING CONDITION
Vehicle
without
monitor
connectorVehicle
with
monitor
connector
±12±No trouble.±±
P070572Transmission range
sensor circuit
Multiple signals inputted simulta-
neously or no signal inputted while
2 driving
cycles
Not
applicablesensor circuit
malfunction
neously or no signal in utted while
running at 60 km / h or more.
cyclesa licable
P071576Input / Turbine speed
sensor circuit
malfunctionInput shaft revolution speed is lower
than specified value while
vehicle is running with ªDº range and
specified engine speed or higher.2 driving
cyclesNot
applicable
P072075Output speed sensor
circuit malfunctionOutput speed sensor signal not
inputted while VSS signal being
inputted.2 driving
cyclesNot
applicable
*1
P0741
Not
applicableTCC (lock-up) solenoid
performance or stack
offActual TCC operation does not
agree with ON / OFF control from
PCM to TCC.2 driving
cyclesNot
applicable
P074365
66TCC (lock-up)
solenoid electricalMonitor signal OFF is detected
When TCC control solenoid is ON or
monitor signal ON is detected when
it is OFF.1 driving
cycleNot
applicable
*1
P0751
Not
applicableShift solenoid A (#1)
performance or stuck
offGear change control from PCM to
A / T does not agree with actual gear
position of A / T.2 driving
cyclesNot
applicable
P075361
62Shift solenoid A (#1)
electricalMonitor signal OFF is detected
when shift solenoid A (#1) is ON or
monitor signal ON is detected when
it is OFF.1 driving
cycleNot
applicable
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-25
DIAGNOSTIC TROUBLE CODE (DTC) TABLE (A / T RELATED CODE) (cont'd)
DTC NO.MIL
Using
scan toolNot using
scan toolDETECTED ITEMDETECTING CONDITION
Vehicle
without
monitor
connectorVehicle
with
monitor
connector
*1
P0756
Not
applicableShift solenoid B (#2)
performance or stuck
offGear change control from PCM to
A / T does not agree with actual gear
position of A / T.2 driving
cyclesNot
applicable
P075863
64Shift solenoid B (#2)
electricalMonitor signal OFF is detected
when shift solenoid B (#2) is ON or
monitor signal ON is detected when
it is OFF.1 driving
cycleNot
applicable
*1
P1875
Not
applicable4WD low switch circuit
malfunctionDifference between vehicle speed
detected by VSS and vehicle speed
detected by output speed sensor
and compensated by 4WD low
switch is larger than specification.2 driving
cyclesNot
applicable
NOTE:
*1: Applicable to vehicle without monitor connector only.
FAIL-SAFE TABLE
When any of the following DTC is detected, ECM (PCM) enters fail-safe mode as long as malfunction continues
to exist but that mode is canceled when ECM detects normal condition after that.
DTC NO.
Using
scan toolNot using
scan toolTROUBLE AREAFAIL SAFE OPERATION
P0177
P011814
15ECT SENSOREach control except 4-A / T is permitted on the basis of
30.1C engine coolant temp.
4-A / T control is performed assuming 31C (engine warmed
up) or higher after 15 min. from engine start.
P0122
P012321
22TP SENSOREach control except 4-A / T is performed on the basis of 124
throttle valve opening.
4-A / T control is performed on the basis of 0 throttle valve
opening.
P070572TR SWITCHA / T control is performed in priority order of L, 2, N, D, R
and P.
P072075OUTPUT SPEED
SENSOR CIRCUIT
MALFUNCTIONA / T control is performed by using signal from VSS.
P075361
62SHIFT SOLENOID
A (#1)A / T control using 3rd gear is performed when D range, 1st
or 2nd gear is used.
TCC solenoid OFF.
P075863
64SHIFT SOLENOID
B (#2)A / T control using 4th gear is performed when D range 2nd
or 3rd gear is used.
When both shift solenoid A (#1) and B (#2) failed
simultaneously, A / T control using 4th gear is always
performed in D range.
TCC solenoid OFF.
P074365
66TCC (Lock-up)
SOLENOIDTCC (lock-up) solenoid OFF.
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
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.