YH4
GRAND
VITARA
1. Fluid pressure check hole
2. Oil pan
1. Oil pan
2. Exhaust pipe
7B1-54 AUTOMATIC TRANSMISSION (4 A / T)
LINE PRESSURE TEST
Purpose of this test is to check operating conditions of each part by
measuring fluid pressure in fluid pressure line. Line pressure test
requires following conditions.
Automatic fluid is at normal operating temperature (70 to 80C /
158 ± 176F).
Fluid is filled to proper level (between FULL HOT and LOW HOT
on dipstick).
1) Apply parking brake securely and place checks against wheels.
2) Attach oil pressure gauge to fluid pressure check hole in trans-
mission case.
Special Tool
(A): 09925-37810
CAUTION:
After attaching oil pressure gauge, check that not fluid
leakage exists.
3) Depress foot brake fully, run engine at idle and stall and then
check fluid pressure in ªDº or ªRº range.
CAUTION:
Do not continue running engine at stall speed longer than
5 seconds.
G16 Engine
Engine runningLine pressuregg
modeªDº rangeªRº range
At idle speed3.9 ± 4.4 kg / cm2
55 ± 63 psi
5.1 ± 5.7 kg / cm2
73 ± 81 psi
At stall speed11.7 ± 13.2 kg / cm2
166 ± 188 psi
14.2 ± 16.7 kg / cm2
202 ± 237 psi
J20 Engine
Engine runningLine pressuregg
modeªDº rangeªRº range
At idle speed3.8 ± 4.3 kg / cm2
54 ± 61 psi
5.3 ± 5.9 kg / cm2
75 ± 84 psi
At stall speed9.7 ± 11.2 kg / cm2
138 ± 159 psi
12.9 ± 15.5 kg / cm2
183 ± 220 psi
H25 Engine
Engine runningLine pressuregg
modeªDº rangeªRº range
At idle speed3.9 ± 4.4 kg / cm2
55 ± 63 psi
6.6 ± 7.2 kg / cm2
94 ± 102 psi
At stall speed11.3 ± 12.7 kg / cm2
161 ± 181 psi
14.7 ± 22.7 kg / cm2
209 ± 323 psi
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-55
Check resultPossible cause
Line pressure higher
than standard level in
each rangeMalfunctioning regulator valve
Malfunctioning throttle valve
Maladjusted A / T throttle cable
Line pressure lower than
standard level in each
rangeDefective O/D clutch
Defective oil pump
Malfunctioning throttle valve
Malfunctioning regulator value
Maladjusted A / T throttle cable
Line pressure lower than
standard level only in ªDº
rangeFluid leakage from forward clutch
Defective O/D clutch
Leakage from ªDº range fluid pressure cir-
cuit
Line pressure lower than
standard level only in ªRº
rangeFluid leakage from direct clutch
Defective O/D clutch
Fluid leakage from reverse brake
Fluid leakage from ªRº range fluid circuit
Tightening torque of transmission case plug:
17 N.m (1.7 kg-m, 12.0 lb-ft)
STALL TEST
This test is to check overall performance of automatic transmission
and engine by measuring stall speed at ªDº and ªRº ranges. Be sure
to perform this test only when transmission fluid is at normal operat-
ing temperature and its level is between FULL and LOW marks.
CAUTION:
Do not run engine at stall more than 5 seconds continu-
ously, for fluid temperature may rise excessively high.
After performing stall test, be sure to leave engine running
at idle for longer than 30 seconds before another stall test.
1) Apply parking brake and block wheels.
2) Install tachometer.
3) Start engine with select lever shifted to ªPº.
4) Depress brake pedal fully.
5) Shift select lever to ªDº and depress accelerator pedal fully while
watching tachometer. Read engine rpm quickly when it has be-
come constant (stall speed).
6) Release accelerator pedal immediately after stall speed is
checked.
7) In the same way, check stall speed in ªRº range.
YH4
GRAND
VITARA
7B1-56 AUTOMATIC TRANSMISSION (4 A / T)
8) Stall speed should be within the following specification.
Stall speed: 2,100 ± 2,400 r / min. for G16 engine
2,300 ± 2,600 r / min. for J20 engine
2,300 ± 2,600 r / min. for H25 engine
Check result
Possible cause
Lower than standard
levelFaulty engine output
Defective torque converter
Higher than standard
level in ªDº rangeSlippery O/D clutch
Slippery forward clutch
Malfunctioning O/D one-way clutch
Malfunctioning one-way clutch No. 2
Low line pressure
Higher than standard
level in ªRº rangeSlippery direct clutch
Slippery reverse brake
Low fluid pressure
Slippery O/D clutch
Defective O/D one-way clutch
ROAD TEST
This test is to check if upshift and downshift take place at specified
speed while actually driving vehicle on a level road.
WARNING:
Carry out test in very little traffic area to prevent an acci-
dent.
Test requires 2 persons, a driver and a tester.
1) Warm up engine.
2) With engine running at idle, shift select lever ªDº.
3) Accelerate vehicle speed by depressing accelerator pedal grad-
ually.
4) While driving in ªDº range, check if gear shift occurs properly as
shown in Gear Shift Diagram in this section.
Test result
Possible cause
When 1 2 upshift fails to
occur1±2 shift valve stuck
When 2 3 upshift fails to
occur2±3 shift valve stuck
When 3 O/D upshift
fails to occur3±4 shift valve stuck
When gear shift point is in-
correctMaladjusted throttle cable
Defective shift solenoid valve
-A or -B
1±2, 2±3 or 3±4 shift valve not
operating properly
YH4
GRAND
VITARA
1
1. Shift solenoids connector
AUTOMATIC TRANSMISSION (4 A / T) 7B1-57
MANUAL ROAD TEST
This test check the gear being used in ªLº, ª2º or ªDº range when
driven with unoperated gear shift control system. Test drive vehicle
on a level road.
NOTE:
Before this test, check diagnostic trouble code (DTC).
1) Disconnect coupler of shift solenoid valves on transmission.
WARNING:
To avoid the danger of being burned, do not touch the hot
exhaust system when disconnecting shift solenoid
valves coupler.
2) With select lever in ªPº, start engine and warm it up.
3) With select lever in ªLº range, start vehicle and accelerate to 20
km/h (12.5 mile/h). Check in this state that 1st gear is being
used.
4) At 20 km/h (12.5 mile/h), shift select lever to 2 range and acceler-
ate to 40 km/h (25 mile/h). Check in this state that 3rd gear is
being used.
5) At 40 km/h (25 mile/h), shift select lever to D range and check
that O/D gear is used when speed is higher than 40 km/h (25
mile/h).
6) After above checks, stop vehicle then engine, and connect shift
solenoids coupler with ignition switch OFF.
WARNING:
To avoid the danger of being burned, do not touch the hot
exhaust system when connecting shift solenoid valves
coupler.
7) Clear DTC with scan tool.
TIME LAG TEST
This test is to check conditions of clutch, reverse brake and fluid
pressure. ªTime lagº means time elapsed since select lever is
shifted with engine idling till shock is felt.
1) With chocks placed before and behind front and rear wheels re-
spectively, depress brake pedal.
2) Start engine.
3) With stop watch ready, shift select lever from ªNº to ªDº range
and measure time from that moment till shock is felt.
4) Similarly measure time lag by shifting select lever from ªNº to ªRº
range.
Specification for ªNºªDºLess than 1.2 sec.
time lagªNºªRºLess than 1.5 sec.
NOTE:
When repeating this test, be sure to wait at least minute
after select lever is shifted back to ªNº range.
Engine should be warmed up fully for this test.
Test resultPossible causes
When ªNºªDº time lag
exceeds specificationLow line pressure
Worn forward clutch
When ªNºªRº time lag
exceeds specificationLow line pressure
Worn direct clutch
Worn reverse brake
YH4
GRAND
VITARA
1. Dipstick (G16 / J20)
2. Dipstick (H25)
AUTOMATIC TRANSMISSION (4 A / T) 7B1-59
ON-VEHICLE SERVICE
MAINTENANCE SERVICE
FLUID LEVEL
LEVEL CHECK AT NORMAL OPERATING TEMPERATURE
1) Stop vehicle and place it level.
2) Apply parking brake and place chocks against wheels.
3) With selector at P position, start engine.
4) Warm up engine till fluid temperature reaches normal operating
temperature (70 ± 80C / 158 ± 176F). As a guide to check fluid
temperature, warm up engine till engine coolant temperature
meter indicated around 1 unit above ªCº point.
5) Keep engine idling and shift selector slowly to L and back to P
position.
6) With engine idling, pull out dipstick, wipe it off with a clean cloth
and put it back into place.
7) Pull out dipstick again and check fluid level indicated on it. Fluid
level should be between FULL HOT and LOW HOT. If it is below
LOW HOT, add an equivalent of DEXRON-III up to FULL HOT.
Fluid specification
An equivalent of DEXRON-III
NOTE:
DO NOT RACE ENGINE while checking fluid level, even af-
ter the engine start.
DO NOT OVERFILL. Overfilling can causes foaming and
loss of fluid through breather. Then slippage and trans-
mission failure can result.
Bringing the level from LOW HOT to FULL HOT requires
0.3 liters (0.64/0.53 US/lmp.pt).
If vehicle was driven under high load such as pulling a
trailer, fluid level should be checked about half an hour af-
ter it is stopped.
YH4
GRAND
VITARA
1. Dipstick (G16 / J20)
2. Dipstick (H25)
1. Drain plug
2. Propeller shaft
1. Dipstick (G16 / J20)
2. Dipstick (H25)
7B1-60 AUTOMATIC TRANSMISSION (4 A / T)
LEVEL CHECK AT ROOM TEMPERATURE
The fluid level check at room temperature performed after repair or
fluid change before test driving is just preparation for level check of
normal operating temperature. The checking procedure itself is the
same as that described previously. If the fluid level is between FULL
COLD and LOW COLD, proceed to test drive. And when the fluid
temperature has reached the normal operating temperature, check
fluid level again and adjust it as necessary.
FLUID CHANGE
1) Lift up vehicle.
2) With engine is cool, remove drain plug from oil pan and drain A / T
fluid.
3) Install drain plug.
Tightening Torque
(a): 23 N
.m (2.3 kg-m, 17.0 lb-ft)
4) Lower vehicle and fill proper amount of an equivalent of DEX-
RON-III.
5) Check fluid level according to procedure described under LEV-
EL CHECK NORMAL OPERATING TEMPERATURE.
Fluid specification
An equivalent of DEXRON-III
Fluid capacity
When draining
from drain plug
hole
2.5 liters (5.28/4.40 US/lmp.pt.)
When
overhauling
6.9 liters (14.58/12.14 US/lmp.pt.)
for G16
7.1 liters (15.00/12.50 US/lmp.pt.)
for J20 / H25
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-65
1. Drain plug
2. Propeller shaft
1. Oiler (with transmission fluid)
2. Solenoid valve
3. BatteryA: Hole (Should be dry)
B: Exhausting fluid Terminal Arrangement of PCM Coupler
(Viewed from harness side)
WITH BATTERY VOLTAGE WITHOUT BATTERY VOLTAGE
H25 Engine
Shift solenoid valve ± A (#1)C51-1-6
Shift solenoid valve ± B (#2)C51-1-1
TCC (Lock-up) solenoid valveC51-1-2
REMOVAL
1) Pull out dipstick and lift up vehicle.
2) With engine cooled, remove drain plug from oil pan and drain
A / T fluid.
3) Install drain plug with gasket.
Tightening Torque
(a): 23 N
.m (2.3 kg-m, 17.0 lb-ft)
4) Remove exhaust pipe bracket and disconnect front propeller
shaft from front differential (if equipped).
5) Remove oil pan bolts.
6) Remove oil pan.
7) Remove oil tubes.
8) Remove solenoid valve No.1 (shift solenoid valve A and B) or so-
lenoid valve No.2 (TCC solenoid valve).
OPERATION CHECK
Whenever shift solenoid valves and TCC (lock-up) solenoid valve
are removed from transmission, verify their valve function physical-
ly before they are reinstalled.
1) Apply oiler to solenoid valve and give compression by hands
and then check to be sure that transmission fluid from oiler does
not come out of holes in solenoid valve when battery voltage is
not conducted.
2) Under the same conditions as above, conduct battery voltage
and then make sure that fluid comes out with vigor.
NOTE:
If fluid does not come out with vigor in above step 2 in-
spection, do not re-use that solenoid valve.
Figure at the left shows shift solenoid valve check.
Check TCC solenoid valve also in the same way.
YH4
GRAND
VITARA
7B1-66 AUTOMATIC TRANSMISSION (4 A / T)
14
2
3
INSTALLATION
Reverse removal procedure to install solenoid valves and noting
the following points.
For details of solenoid valve installation, refer to ªUnit Repairº
section. Use new gasket and O-ring.
Install oil tubes in such order as shown in figure.
For details of oil pan installation, refer to ªUnit Repairº section.
Use new oil pan gasket.
Tighten universal joint flange bolts & nuts and exhaust pipe brack-
et bolts to specified torque.
Fill A / T fluid and check fluid level according to procedure de-
scribed in ªCHANGING FLUIDº previously.
Check for fluid leakage after warming up A / T.
THROTTLE POSITION SENSOR
INSPECTION
Refer to SECTION 6E1 / 6E2 for inspection.
POWER / NORMAL CHANGE SWITCH
INSPECTION
Check Power / Normal change switch for operation referring to Step
4 of Diag. Flow Table B-4 in this section.
If malfunction is found, replace.