AUTOMATIC TRANSAXLE
K2–43
K2
When the clutch pressure is not applied
•When the clutch drum rotates, centrifugal force acts on the residual ATF in the clutch chamber to push against
the piston. However, centrifugal force also acts on the ATF filled in the centrifugal balance clutch chamber to
push back the piston. As a result, the two forces are eliminated and the piston remains stationary, thus
preventing clutch engagement.
When the clutch pressure is applied
•When clutch pressure is applied to the clutch chamber, the clutch pressure overcomes the oil pressure and the
spring force in the opposite centrifugal balance clutch chamber, and pushes the piston to engage the clutches.
Because the centrifugal force acting on the clutch pressure in the clutch chamber is canceled by another
centrifugal force acting on the ATF filled in the centrifugal balance clutch chamber, the influence of the
centrifugal force created by the clutch drum revolution speed is eliminated. As a result, stable piston pushing
force is obtained in all rotation ranges, and smoother shifts can be made.
End Of SieCONTROL VALVE BODY DESCRIPTIONA6E571421100201Outline
•The control valve body is composed of four bodies: the sub lower body, lower body, internal body, and the upper
body.
•To minimize the component in the control valve body, clutch engagement is electronically controlled, hydraulic
circuits were simplified and the valve types reduced.
AMU0517S019
AUTOMATIC TRANSAXLE
K2–49
K2
ON/OFF type (two-way)
Normal low
•De-energized (OFF)
—The TCM does not apply an electric current to the solenoid valves. The rod moves upward by hydraulic
pressure and the drain port opens.
•Energized (ON)
—The TCM applies an electric current to the solenoid valves. This excites the coil and forces the rod to move
downward to retain hydraulic pressure.
End Of Sie
AMU0517S027
LOCATION INDEX
K2–71
K2
End Of Sie
1 Automatic transaxle fluid (ATF)
(See K2–78 AUTOMATIC TRANSAXLE FLUID
(ATF) INSPECTION)
(See K2–80 AUTOMATIC TRANSAXLE FLUID
(ATF) REPLACEMENT)
2 Transaxle range (TR) switch
(See K2–80 TRANSAXLE RANGE (TR) SWITCH
INSPECTION)
(See K2–81 TRANSAXLE RANGE (TR) SWITCH
REMOVAL/INSTALLATION)
(See K2–83 TRANSAXLE RANGE (TR) SWITCH
ADJUSTMENT)
3 Transaxle fluid temperature (TFT) sensor
(See K2–84 TRANSAXLE FLUID TEMPERATURE
(TFT) SENSOR INSPECTION)
(See K2–85 TRANSAXLE FLUID TEMPERATURE
(TFT) SENSOR REMOVAL/INSTALLATION)
4 Input/turbine speed sensor
(See K2–85 INPUT/TURBINE SPEED SENSOR
INSPECTION)
(See K2–86 INPUT/TURBINE SPEED SENSOR
REMOVAL/INSTALLATION)
5 Intermediate sensor
(See K2–86 INTERMEDIATE SENSOR
INSPECTION)
(See K2–86 INTERMEDIATE SENSOR REMOVAL/
INSTALLATION)
6 Vehicle speedometer sensor (VSS)
(See K2–87 VEHICLE SPEEDOMETER SENSOR
(VSS) INSPECTION)
(See K2–87 VEHICLE SPEEDOMETER SENSOR
(VSS) REMOVAL/INSTALLATION)
7 Solenoid valve
(See K2–88 SOLENOID VALVE INSPECTION)
(See K2–90 SOLENOID VALVE REMOVAL/
INSTALLATION)
8TCM
(See K2–90 TCM INSPECTION)
(See K2–96 TCM REMOVAL/INSTALLATION)9 Transfer oil
(See K2–114 TRANSFER OIL INSPECTION)
(See K2–114 TRANSFER OIL REPLACEMENT)
10 Automatic transaxle
(See K2–99 AUTOMATIC TRANSAXLE AND
TRANSFER REMOVAL/INSTALLATION)
11 Transfer
(See K2–115 TRANSFER REMOVAL/
INSTALLATION)
(See K2–116 BREATHER PLUG REMOVAL/
INSTALLATION)
12 Oil seal
(See K2–104 OIL SEAL REMOVAL/
INSTALLATION)
13 Control valve body
(See K2–105 CONTROL VALVE BODY REMOVAL/
INSTALLATION)
14 Oil cooler
(See K2–106 OIL COOLER FLUSHING)
(See K2–108 OIL COOLER REMOVAL/
INSTALLATION)
(See K2–110 OIL COOLER DISASSEMBLY/
ASSEMBLY)
15 Drive plate
(See K2–112 DRIVE PLATE REMOVAL/
INSTALLATION)
16 Selector lever
(See K2–117 SELECTOR LEVER INSPECTION)
(See K2–117 SELECTOR LEVER COMPONENT
INSPECTION)
(See K2–119 SELECTOR LEVER REMOVAL/
INSTALLATION)
(See K2–122 SELECTOR LEVER DISASSEMBLY/
ASSEMBLY)
17 Selector cable
(See K2–118 SELECTOR CABLE ADJUSTMENT)
K2–72
AUTOMATIC TRANSAXLE
MECHANICAL SYSTEM TESTA6E571401030209Mechanical System Test Preparation
1. Apply the parking brake and use wheel chocks at the front and rear of the wheels.
2. Inspect the engine coolant. (See Section E.)
3. Inspect the engine oil. (See D–8 ENGINE OIL INSPECTION.)
4. Inspect the ATF levels. (See K2–79 Automatic Transaxle Fluid (ATF) Level Inspection.)
5. Inspect the idle speed and ignition timing in P position. (See F1–22 IDLE SPEED INSPECTION (4WD).)
Line Pressure Test
Note
•Line pressure cannot be measured on the JA5AX-EL automatic transaxle. Measure the low clutch
pressure in place of D and M range line pressures. Measure the reverse clutch pressure in place of R
position line pressure.
1. Engine idling.
(1) Perform mechanical system test preparation. (See K2–72 Mechanical System Test Preparation.)
Warning
•Removing the plug when the ATF is hot can be dangerous. Hot ATF can come out of the opening
and badly burn you. Before removing the square-head plug, allow the ATF to cool.
(2) Remove the plug and O-ring shown in the
figure.
AUTOMATIC TRANSAXLE
LINE PRESSURE INSPECTION PORT
D,M RANGES
FRONT
A6E5714W101
LINE PRESSURE INSPECTION PORT
R POSITION
FRONT
A6E5714W102
K2–74
AUTOMATIC TRANSAXLE
Evaluation of line pressure test
Stall Speed Test
1. Perform mechanical system test preparation. (See K2–72 Mechanical System Test Preparation.)
2. Connect a tachometer.
3. Start the engine.
4. Shift the selector lever to D range.
Caution
•Do not maintain WOT in any gear range for more than 5 seconds or transaxle damage will occur.
•If engine speed recorded by the tachometer exceeds maximum specified rpm, release the
accelerator pedal immediately. Clutch or band slippage is indicator.
5. Firmly depress the brake pedal with the left foot, and gently depress the accelerator pedal to the floor (WOT)
with the right.
6. When the engine speed no longer increases, quickly read the engine speed and release the accelerator pedal.
7. Shift the selector the to N position and let the engine idle for 1 minute or more to cool the ATF.
8. Perform stall tests for the remaining ranges and position in the same manner.
•R position
•Mrange (1GR, 2GR)
Engine stall speed
ATF temperature : 60—70 °C {140—158 °F}
Turn off all electrical loads
2,200—2,600 rpm
9. Turn off the engine.
Evaluation of stall test
Condition Possible cause
IdleBelow specificationLow pressure in all rangesWorn oil pump
Poor operation of each solenoid
Fluid leaking from oil strainer, oil pump, pressure regulator
valve, torque converter relief valve, and/or pressure relief valve
Pressure regulator valve or pilot valve sticking
Damaged pressure regulator valve spring or pilot valve spring
Low pressure in D and M
rangeFluid leaking from hydraulic circuit of low clutch
Low pressure in R position
onlyFluid leaking from hydraulic circuit of reverse clutch
Fluid leaking from hydraulic circuit of low and reverse brake
clutch
Above specification High pressure in all rangesThrottle position sensor out of adjustment
TFT sensor malfunction
Poor operation of shift solenoid
Pilot valve sticking
Pressure reducing valve or plug sticking
Stall Below specification Low pressure in all rangesThrottle position sensor out of adjustment
Pressure control solenoid malfunction
Poor operation of shift solenoid
Pilot valve sticking
Pressure reducing valve or plug sticking
Condition Possible cause
Above specificationIn all forward ranges and R
positionInsufficient line pressure
Worm oil pump
Poor operation of low clutch
Poor adjustment or malfunction of TR switch
Oil leaking from oil pump, control valve, and/or transmission
case
Pressure regulator valve or pilot valve sticking
In all forward ranges Low clutch slippage
Low one-way clutch slippage
Reduction one-way clutch slippage
In R positionLow and reverse brake slippage
Reverse clutch slippage
Reduction brake slippage
Below specificationIn all forward ranges and R
positionEngine out of tune
One-way clutch slippage within torque converter
AUTOMATIC TRANSAXLE
K2–75
K2
Time Lag Test
1. Perform mechanical system test preparation. (See K2–72 Mechanical System Test Preparation.)
2. Start the engine.
3. Warm up the engine until the ATF temperature reaches 60—70°C {140—158°F}. Shift the selector lever from N
position to D range.
4. Use a stopwatch to measure the time it takes from shifting until engagement is felt. Take three measurements
for each test and average the results using the following formula.
Formula
Average time lag = (Time 1 + Time 2 + Time 3) / 3
5. Perform the test for the following shifts in the same manner.
•N position → P position
Time lag
N → D range ... approx. 0.5—1.0 second
N → R position ... approx. 0.6— 1.0 second
Evaluation of time lag test
End Of SieROAD TESTA6E571401030210Road Test Preparation
1. Inspect the engine coolant. (See Section E.)
2. Inspect the engine oil. (See D–8 ENGINE OIL INSPECTION.)
3. Inspect the ATF levels. (See K2–78 AUTOMATIC TRANSAXLE FLUID (ATF) INSPECTION.)
4. Inspect the idle speed and ignition timing in P position. (See F1–22 IDLE SPEED INSPECTION (4WD).)
5. Bring up the engine and transaxle to normal operating temperature.
Shift Diagram
D range (normal mode)
Condition Possible Cause
Above specificationN → D shiftInsufficient line pressure in all forward ranges
Low clutch slippage
Low one-way clutch slippage
Reduction one-way clutch slippage
N → R shiftInsufficient line pressure in R position
Low and reverse brake slippage
Reverse clutch slippage
Reduction brake slippage
0/8 1/8
2/8
3/8
4/8
5/8
6/8
7/8
8/8
TCC OPERATION AVAILABLE
VEHICLE SPEED km/h {mph}
THROTTLE OPENING
SHIFT UP
4GR
TCC
OFF
SHIFT DOWN
0
{0}20
{12}40
{25}60
{37}80
{50}100
{63}120
{75}140
{87}160
{99}180
{112}220
{137} 200
{124} 112 23
2
2 232
34
4534
45
5GR TCC ON
4GR TCC ON
5GR TCC OFF
A6E5714W104
K2–78
AUTOMATIC TRANSAXLE
Evaluation
End Of SieAUTOMATIC TRANSAXLE FLUID (ATF) INSPECTIONA6E571419001201Automatic Transaxle Fluid (ATF) Condition Inspection
1. One way of determining whether the transaxle should be replaced is by noting:
•If the ATF is muddy or varnished.
•If the ATF smells strange or unusual.
ATF Condition
Condition Possible Cause
No 1-2 up- or downshiftStuck shift solenoid C
Stuck shift valve C
Wore 2-4 brake
Trouble intermediate sensor
No 2-3 up- or downshiftStuck shift solenoid A
Stuck shift valve A
Wore high clutch
No 3-4 up- or downshiftStuck shift solenoid B
Stuck shift valve B
Wore 2-4 brake
No 4-5 up- or downshiftStuck shift solenoid A
Stuck shift valve A
Wore direct clutch
Trouble TFT
TCC non operation shiftStuck TCC solenoid valve
Stuck TCC valve
Incorrect shift pointTrouble VSS output signal
Trouble TR switch
Trouble TP signal and engine torque signal
Excessive shift shock slippageStuck pressure control solenoid
Stuck pressure regulator valve
Stuck pressure modifier valve
Stuck accumulator valve A, B, or C
Stuck 2-4 brake solenoid valve
Stuck high clutch solenoid valve
Stuck low clutch accumulator
Stuck 2-4 brake accumlator
Stuck high clutch accumlator
Stuck direct clutch accumlator
Stuck reduction accumlator
Trouble VSS
No Engine braking effect Wore reduction brake band
Stuck reduction reducing valve
Stuck reduction timing valve
Stuck reduction timing solenoid valve
Condition Possible cause
Clear dark red Normal—
Light red (pink) Contaminated with water•Broken oil cooler inside of radiator
•Poor filler tube installation:
Problem could be occurring to parts inside the
transaxle by water contamination. If necessary,
exchange transaxle.
Reddish
brownHas burnt smell and metal
specs are foundDeteriorated ATFDefect powertrain components inside of transaxle:
Specks cause wide range of problems by plugging up
in oil pipe, control valve body and oil cooler in radiator.
•When large amount of metal specks are found.
Exchange transaxle if necessary.
•Implement flushing operation as there is a
possibility to have specks plugging up oil pipe and/
or oil cooler inside of radiator.
Has no burnt smell Normal•Discoloration by oxidation
AUTOMATIC TRANSAXLE
K2–79
K2
Automatic Transaxle Fluid (ATF) Level Inspection
Caution
•The ATF amount varies according to ATF's temperature. Therefore, when checking the ATF level or
replacing the ATF, use a thermometer to measure the temperature then adjust the ATF amount to
the specified level according to the specified temperature.
1. Park the vehicle on level ground.
2. Apply the parking brake and position wheel chocks securely to prevent the vehicle from rolling.
3. Adjust the length of the thermistor probe measure to the measure same as the dipstick and hold the probe with
a paper holder.
4. Insert into the filler tube and measure the
temperature.
5. Warm up the engine until the ATF reaches (60—
70 °C {140—158 °F}).
Caution
•Do not warm the transaxle by performing
stalls. This will damage the torque
converter.
Note
•In some cases it may be necessary to
inspect the ATF in the cool range 15—25 °C
{59—77 °F} before warming up the engine.
6. While depressing the brake pedal, shift the selector lever to each range (P—M), pausing momentarily in each
range.
7. Shift back to P position.
Note
•If the ATF level is too high or too low in hot condition, the following problems may be the cause.
8. While the engine is idling, verify that the ATF level
is in the HOT (65 °C {149 °F}) range. Add the
ATF specified type of, if necessary. (See K2–80
AUTOMATIC TRANSAXLE FLUID (ATF)
REPLACEMENT.)
ATF type
ATF M-III or equivalent (e.g. Dexron
®III)
Capacity (Approximate quantity)
8.3 L {8.8 US qt, 7.3 Imp qt}
End Of Sie
ATF level Condition Possible cause
Too lowLine pressure is
lower than the
specificationAir in transaxle oil passage
due to slipping or damaged
clutch mechanism
Too high ATF is hotATF deteriorated due to
slipping clutch or stuck
valve
A6E5614W003
A6E5714W105