AT-4
Diagnosis Procedure .............................................210
KEY INTERLOCK CABLE ...............................213
Removal and Installation .......................................213
ON-VEHICLE SERVICE ..................................216
Control Valve Assembly and Accumulators ...........216
Park/Neutral Position (PNP) Switch ......................219
Revolution Sensor .................................................221
Turbine Revolution Sensor (Power Train Revolu-
tion Sensor) ...........................................................
222
Differential Side Oil Seal ........................................223
AIR BREATHER HOSE ...................................225
Removal and Installation .......................................225
TRANSAXLE ASSEMBLY ..............................226
Removal and Installation .......................................226
OVERHAUL .....................................................230
Component ............................................................230
Oil Channel ............................................................237
Location of Adjusting Shims, Needle Bearings and
Thrust Washers .....................................................
238
Location of Snap Rings .........................................239
DISASSEMBLY ...............................................240
Disassembly ..........................................................240
REPAIR FOR COMPONENT PARTS ..............257
Manual Shaft .........................................................257
Oil Pump ................................................................260
Control Valve Assembly ........................................263
Control Valve Upper Body .....................................272
Control Valve Lower Body .....................................276
Reverse Clutch ......................................................279
High Clutch ............................................................284
Forward and Overrun Clutches .............................288
Low & Reverse Brake ............................................295
Rear Internal Gear and Forward Clutch Hub .........299
Output Shaft, Output Gear, Idler Gear, Reduction
Pinion Gear and Bearing Retainer .........................
302
Band Servo Piston Assembly ................................307
Final Drive .............................................................313
ASSEMBLY ......................................................318
Assembly (1) .........................................................318
Adjustment (1) .......................................................319
Assembly (2) .........................................................325
Adjustment (2) .......................................................330
Assembly (3) .........................................................333
SERVICE DATA AND SPECIFICATIONS
(SDS) ................................................................
341
General Specification ............................................341
Vehicle Speed at Which Gear Shifting Occurs .....341
Vehicle Speed at When Lock-up Occurs/Releases
.
341
Stall Speed ............................................................341
Line Pressure ........................................................341
Adjusting shims, Needle Bearings, Thrust Wash-
ers and Snap Rings ..............................................
341
Control Valves .......................................................343
Accumulator ..........................................................343
Clutches and Brakes .............................................343
Final Drive .............................................................345
Planetary Carrier ...................................................345
Oil Pump ...............................................................345
Input Shaft .............................................................345
Reduction Pinion Gear ..........................................345
Band Servo ...........................................................345
Output Shaft ..........................................................346
Bearing Retainer ...................................................346
Total End Play .......................................................346
Reverse Clutch End Play ......................................346
Removal and Installation .......................................346
Shift Solenoid Valves ............................................346
Solenoid Valves ....................................................346
A/T Fluid Temperature Sensor ..............................347
Revolution Sensor .................................................347
Dropping Resistor .................................................347
Turbine Revolution Sensor (Power Train Revolu-
tion Sensor) ...........................................................
347
AT-34
< SERVICE INFORMATION >
A/T CONTROL SYSTEM
Control Valve
INFOID:0000000001703170
FUNCTION OF CONTROL VALVES
Centrifugal Cancel MechanismINFOID:0000000001703171
FUNCTION
The centrifugal cancel mechanism is a mechanism to cancel the centrifugal hydraulic pressure instead of the
conventional check balls. It cancels the centrifugal hydraulic pressure which is generated as high clutch drum
rotates, and it allows for preventing high clutch from dragging and for providing stable high clutch piston press-
ing force in all revolution speeds.
STRUCTURE/OPERATION
Valve name Function
Pressure regulator valve, plug and sleeve
plugRegulates oil discharged from the oil pump to provide optimum line pressure for all driving
conditions.
Pressure modifier valve and sleeve Used as a signal supplementary valve to the pressure regulator valve. Regulates pres-
sure-modifier pressure (signal pressure) which controls optimum line pressure for all driv-
ing conditions.
Pilot valve Regulates line pressure to maintain a constant pilot pressure level which controls lock-up
mechanism, overrun clutch, shift timing.
Accumulator control valve Regulates accumulator back-pressure to pressure suited to driving conditions.
Manual valve Directs line pressure to oil circuits corresponding to select positions.
Hydraulic pressure drains when the shift lever is in Neutral.
Shift valve A Simultaneously switches three oil circuits using output pressure of shift solenoid valve A
to meet driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and upshifting (1st → 2nd → 3rd → 4th gears/4th → 3rd
→ 2nd → 1st gears) in combination with shift valve B.
Shift valve B Simultaneously switches two oil circuits using output pressure of shift solenoid valve B in
relation to driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and upshifting (1st → 2nd → 3rd → 4th gears/4th → 3rd
→ 2nd → 1st gears) in combination with shift valve A.
Overrun clutch control valve Switches hydraulic circuits to prevent engagement of the overrun clutch simultaneously
with application of the brake band in D
4. (Interlocking occurs if the overrun clutch engages
during D
4.)
1st reducing valve Reduces low & reverse brake pressure to dampen engine-brake shock when downshift-
ing from the 1st position 1
2 to 11.
Overrun clutch reducing valve Reduces oil pressure directed to the overrun clutch and prevents engine-brake shock.
In the 1st and 2nd positions, line pressure acts on the overrun clutch reducing valve to
increase the pressure-regulating point, with resultant engine brake capability.
Torque converter relief valve Prevents an excessive rise in torque converter pressure.
Torque converter clutch control valve, plug
and sleeveActivates or inactivates the lock-up function.
Also provides smooth lock-up through transient application and release of the lock-up
system.
1-2 accumulator valve and piston Lessens the shock find when the 2nd gear band servo contracts, and provides smooth
shifting.
3-2 timing valve Switches the pace that oil pressure is released depending on vehicle speed; maximizes
the high clutch release timing, and allows for soft downshifting.
Shuttle valve Determines if the overrun clutch solenoid valve should control the 3-2 timing valve or the
overrun clutch control valve and switches between the two.
Cooler check valve At low speeds and with a small load when a little heat is generated, saves the volume of
cooler flow, and stores the oil pressure for lock-up.
AT-52
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Line Pressure
Judgement of Line Pressure Test
Road TestINFOID:0000000001703183
DESCRIPTION
• The purpose of the test is to determine overall performance of A/T
and analyze causes of malfunctions.
• The road test consists of the following three parts:
1. Check before engine is started. Refer to AT- 5 3
.
2. Check at idle. Refer to AT- 5 3
.
3. Cruise test
• Inspection all the item from Part 1 to Part 3. Refer to AT- 5 5
,
AT- 5 8
and AT- 5 9 .
Engine speedLine pressure [kPa (kg/cm
2 , psi)]
D, 2nd and 1st positions R position
Idle speed 500 (5.1, 73) 778 (7.9, 113)
Stall speed 1,173 (12.0, 170) 1,825 (18.6, 265)
Judgement Suspected parts
At idleLine pressure is low in all positions. • Oil pump wear
• Control piston damage
• Pressure regulator valve or plug sticking
• Spring for pressure regulator valve damaged
• Fluid pressure leakage between oil strainer and pressure regulator valve
• Clogged strainer
Line pressure is low in particular posi-
tion.• Fluid pressure leakage between manual valve and particular clutch
• For example, line pressure is:
− Low in “R” and “1” positions, but
− Normal in “D”, and “2” positions.
Therefore, fluid leakage exists at or around low and reverse brake circuit.
Refer to AT- 1 9 , "
Shift Mechanism".
Line pressure is high. • Accelerator pedal position signal malfunction
• A/T fluid temperature sensor damaged
• Line pressure solenoid valve sticking
• Short circuit of line pressure solenoid valve circuit
• Pressure modifier valve sticking
• Pressure regulator valve or plug sticking
• Open in dropping resistor circuit
At stall
speedLine pressure is low. • Accelerator pedal position signal malfunction
• Line pressure solenoid valve sticking
• Short circuit of line pressure solenoid valve circuit
• Pressure regulator valve or plug sticking
• Pressure modifier valve sticking
• Pilot valve sticking
SAT786A
AT-68
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Slips/Will Not EngageRaces extremely fast
or slips in changing
from D
3 to D2 when
depressing accelera-
tor pedal. ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensor EC-493
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Shift solenoid valve BAT- 1 3 9
6. Control valve assemblyAT- 2 1 6
OFF vehicle7. Brake bandAT- 3 0 78. High clutchAT- 2 8 4
Races extremely fast
or slips in changing
from D
4 or D3 to D 1
when depressing ac-
celerator pedal.ON vehicle1. A/T fluid levelMA-22
2. Accelerator pedal position sensorEC-493
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
5. Shift solenoid valve AAT- 1 3 4
6. Shift solenoid valve BAT- 1 3 9
7. Control valve assemblyAT- 2 1 6
OFF vehicle8. Forward clutchAT- 2 8 89. Forward one-way clutchAT- 2 9 9
10. Low one-way clutchAT- 2 4 0
Vehicle will not run in
any position.ON vehicle1. A/T fluid levelMA-22
2. Control cable adjustmentAT- 2 0 7
3. Line pressure testAT- 4 8
4. Line pressure solenoid valveAT- 1 2 9
OFF vehicle5. Oil pumpAT- 2 6 0
6. High clutchAT- 2 8 4
7. Brake bandAT- 3 0 7
8. Low & reverse brakeAT- 2 9 5
9. Torque converterAT- 2 4 0
10. Parking componentsAT- 2 3 0
OthersEngine cannot be
started in “P” and “N”
positions.
AT- 1 7 8
ON vehicle1. Ignition switch and starterPG-3
, SC-8
2. Control cable adjustmentAT- 2 0 7
3. PNP switch adjustmentAT- 2 1 9
Engine starts in posi-
tions other than “P”
and “N”.ON vehicle1. Control cable adjustmentAT- 2 0 7
2. PNP switch adjustmentAT- 2 1 9
Transaxle noise in“ P”
and “N” positions.ON vehicle1. A/T fluid levelMA-22
2. Line pressure testAT- 4 8
3. Accelerator pedal position sensorEC-493
4. Vehicle speed sensor·A/T (Revolution sensor)
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
OFF vehicle5. Oil pumpAT- 2 6 06. Torque converterAT- 2 4 0
Items Symptom Condition Diagnostic item Reference page
AT-70
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
OthersMaximum speed not
attained. Poor accel-
eration.ON vehicle1. A/T fluid levelMA-22
2. PNP switch adjustmentAT- 2 1 9
3. Overdrive control switchAT- 1 6 7
4. Accelerator pedal position sensorEC-493
5. Vehicle speed sensor·A/T (Revolution sensor)
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
6. Shift solenoid valve AAT- 1 3 4
7. Shift solenoid valve BAT- 1 3 9
8. Control valve assemblyAT- 2 1 6
OFF vehicle9. Reverse clutchAT- 2 7 9
10. High clutchAT- 2 8 4
11. Brake bandAT- 3 0 7
12. Low & reverse brakeAT- 2 9 5
13. Oil pumpAT- 2 6 0
14. Torque converterAT- 2 4 0
Transaxle noise in
“D”, “2”, “1” and “R”
positions.ON vehicle 1. A/T fluid levelMA-22
OFF vehicle 2. Torque converterAT- 2 4 0
Engine brake does
not operate in “1” po-
sition.ON vehicle1. PNP switch adjustmentAT- 2 1 9
2. Control cable adjustmentAT- 2 0 7
3. Vehicle speed sensor·A/T (Revolution sensor)
and vehicle speed sensor·MTRAT- 9 6, AT- 1 4 9
4. Control valve assemblyAT- 2 1 6
5. Overrun clutch solenoid valveAT- 1 4 4
OFF vehicle6. Overrun clutchAT- 2 8 87. Low & reverse brakeAT- 2 9 5
Transaxle overheats.ON vehicle1. A/T fluid levelMA-22
2. Engine idling speedEC-73
3. Accelerator pedal position sensorEC-493
4. Line pressure testAT- 4 8
5. Line pressure solenoid valveAT- 1 2 9
6. Control valve assemblyAT- 2 1 6
OFF vehicle7. Oil pumpAT- 2 6 0
8. Reverse clutchAT- 2 7 9
9. High clutchAT- 2 8 4
10. Brake bandAT- 3 0 7
11. Forward clutchAT- 2 8 8
12. Overrun clutchAT- 2 8 8
13. Low & reverse brakeAT- 2 9 5
14. Torque converterAT- 2 4 0
Items Symptom Condition Diagnostic item Reference page
TROUBLE DIAGNOSIS
AT-71
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
TCM Terminal and Reference ValueINFOID:0000000001703192
TCM HARNESS CONNECTOR TERMINAL LAYOUT
Terminals and Reference Values for TCM
TCM terminal data are reference values, measured between each terminal and ground.
OthersATF shoots out during
operation.
White smoke emitted
from exhaust pipe
during operation.ON vehicle 1. A/T fluid levelMA-22
OFF vehicle2. Reverse clutchAT- 2 7 9
3. High clutchAT- 2 8 4
4. Brake bandAT- 3 0 7
5. Forward clutchAT- 2 8 8
6. Overrun clutchAT- 2 8 8
7. Low & reverse brakeAT- 2 9 5
Unusual smell at A/T
fluid charging pipe.ON vehicle 1. A/T fluid levelMA-22
OFF vehicle2. Torque converterAT- 2 4 0
3. Oil pumpAT- 2 6 0
4. Reverse clutchAT- 2 7 9
5. High clutchAT- 2 8 4
6. Brake bandAT- 3 0 7
7. Forward clutchAT- 2 8 8
8. Overrun clutchAT- 2 8 8
9. Low & reverse brakeAT- 2 9 5
Items Symptom Condition Diagnostic item Reference page
WCIA0717E
Te r m i n a lWire
colorItem ConditionJudgement stan-
dard (Approx.)
1WLine pressure solenoid
valveWhen releasing accelerator pedal after
warming up engine.1.5 - 3.0 V
When depressing accelerator pedal ful-
ly after warming up engine.0 V
2PLine pressure solenoid
valve (with dropping re-
sistor)When releasing accelerator pedal after
warming up engine.4 - 14 V
When depressing accelerator pedal ful-
ly after warming up engine.0 V
3GRTorque converter clutch
solenoid valveWhen A/T performs lock-up. 8 - 15 V
When A/T does not perform lock-up. 0 V
5 L CAN H — —
6 P CAN L — —
10 R Power supplyWhen turning ignition switch to “ON”. Battery voltage
When turning ignition switch to “OFF”. 0 V
AT-114
< SERVICE INFORMATION >
DTC P0734 A/T 4TH GEAR FUNCTION
DTC P0734 A/T 4TH GEAR FUNCTION
DescriptionINFOID:0000000001703246
• This malfunction will not be detected while the OD OFF indicator lamp is indicating another self-diagnosis
malfunction.
• This malfunction is detected when the A/T does not shift into fourth gear position or the torque converter
clutch does not lock up as instructed by the TCM. This is not caused by electrical malfunction (circuits open
or shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation,
malfunctioning oil pump or torque converter clutch, etc.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001703247
Remarks: Specification data are reference values.
On Board Diagnosis LogicINFOID:0000000001703248
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P0734 A/T 4TH GR FNCTN” with CONSULT-III is detected when A/T cannot be
shifted to the 4th gear position even if electrical circuit is good.
• This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by TCM
as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th) supposed by TCM, the slip ratio will be much
less than normal. In case the ratio does not reach the specified value, TCM judges this diagnosis malfunc-
tion.
This malfunction will be caused when shift solenoid valve A is stuck open or shift solenoid valve B is stuck
closed.
• Gear positions supposed by TCM are as follows.
In case of gear position with no malfunctions: 1, 2, 3 and 4 positions
In case of gear position with shift solenoid valve A stuck open: 2, 2, 3 and 3* positions
In case of gear position with shift solenoid valve B stuck closed: 1, 2, 2 and 1* positions to each gear position
above
*: “P0734 A/T 4TH GR FNCTN” is detected.
Possible CauseINFOID:0000000001703249
• Shift solenoid valve A
• Shift solenoid valve B
• Line pressure solenoid valve
• Each clutch
• Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000001703250
CAUTION:
• Always drive vehicle at a safe speed.
• If performing this “DTC Confirmation Procedure” again, always turn ignition switch OFF and wait at
least 10 seconds before continuing.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
Gear position 1 2 3 4
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
Item name Condition Display value (Approx.)
LINE PRES DTYSmall throttle opening (Low line pressure) ⇔ Large
throttle opening (High line pressure)0% ⇔ 94%
AT-124
< SERVICE INFORMATION >
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)
DescriptionINFOID:0000000001703260
• This malfunction will not be detected while the OD OFF indicator lamp is indicating another self-diagnosis
malfunction.
• This malfunction is detected when the A/T does not shift into fourth gear position or the torque converter
clutch does not lock-up as instructed by the TCM. This is not caused by electrical malfunction (circuits open
or shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation,
malfunctioning oil pump or torque converter clutch, etc.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001703261
Remarks: Specification data are reference values.
On Board Diagnosis LogicINFOID:0000000001703262
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P0744 A/T TCC S/V FNCTN” with CONSULT-III is detected when A/T cannot per-
form lock-up even if electrical circuit is good.
• This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by TCM
as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th) supposed by TCM, the slip ratio will be much
less than normal. In case the ratio does not reach the specified value, TCM judges this diagnosis malfunc-
tion.
This malfunction will be caused when shift solenoid valve B is stuck closed.
• Gear positions supposed by TCM are as follows.
In case of gear position with no malfunctions: 1, 2, 3 and 4 positions
In case of gear position with shift solenoid valve B stuck closed: 1, 2, 2 and 1* positions to each gear position
above
*: “P0744 A/T TCC S/V FNCTN” is detected.
Possible CauseINFOID:0000000001703263
• Line pressure solenoid valve
• Torque converter clutch solenoid valve
• Each clutch
• Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000001703264
CAUTION:
• Always drive vehicle at a safe speed.
• If performing this “DTC Confirmation Procedure” again, always turn ignition switch OFF and wait at
least 10 seconds before continuing.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-III
1. Start engine and select “DATA MONITOR” mode for “A/T” with CONSULT-III.
2. Touch “START”.
3. Make sure that output voltage of A/T fluid temperature sensor is within the range below.
FLUID TEMP SE: 0.4 - 1.5 V
If out of range, drive vehicle to decrease voltage (warm up the fluid) or stop engine to increase voltage
(cool down the fluid).
4. Select “TCC S/V FNCTN P0744” of “DTC WORK SUPPORT” mode for “A/T” with CONSULT-III and touch
“START”.
Item name Condition Display value (Approx)
TCC S/V DUTY Lock-up OFF ⇔ Lock-up ON 4% ⇔ 94%