Torque Converter Clutch Control Valve OperationNJAT0015S0303
AAT155A
Lock-up released
The OFF-duration of the torque converter clutch solenoid valve is
long, and pilot pressure is high. The pilot pressure pushes the end
face of the torque converter clutch control valve in combination with
spring force to move the valve to the left. As a result, converter
pressure is applied to chamber A (torque converter clutch piston
release side). Accordingly, the torque converter clutch piston
remains unlocked.
Lock-up applied
When the OFF-duration of the torque converter clutch solenoid
valve is short, pilot pressure drains and becomes low. Accordingly,
the control valve moves to the right by the pilot pressure of the
other circuit and converter pressure. As a result, converter pres-
sure is applied to chamber B, keeping the torque converter clutch
piston applied.
Also smooth lock-up is provided by transient application and
release of the lock-up.
OVERRUN CLUTCH CONTROL (ENGINE BRAKE
CONTROL)
NJAT0015S04Forward one-way clutch is used to reduce shifting shocks in down-
shifting operations. This clutch transmits engine torque to the
wheels. However, drive force from the wheels is not transmitted to
the engine because the one-way clutch rotates idle. This means the
engine brake is not effective.
The overrun clutch operates when the engine brake is needed.
Overrun Clutch Operating ConditionsNJAT0015S0401
Selector lever position Gear position Throttle opening
ªDº position D
1,D2,D3gear position
Less than 3/16
ª2º position 2
1,22gear position
ª1º position 1
1,12gear position At any position
SAT014J
OVERALL SYSTEM
Control Mechanism (Cont'd)
AT-34
Diagnostic Worksheet=NJAT0023S0102
1.NRead the Fail-safe and listen to customer complaints. AT-9
2.NCHECK A/T FLUIDAT-78
NLeakage (Follow specified procedure)
NFluid condition
NFluid level
3.NPerform STALL TEST and LINE PRESSURE TEST. AT-78, 82
NStall test Ð Mark possible damaged components/others.
NTorque converter one-way clutch
NReverse clutch
NForward clutch
NOverrun clutch
NForward one-way clutchNLow & reverse brake
NLow one-way clutch
NEngine
NLine pressure is low
NClutches and brakes except high clutch
and brake band are OK
NLine Pressure test Ð Suspected parts:
4.NPerform all ROAD TEST and mark required procedures. AT-83
4-1. Check before engine is started. AT-85
NSELF-DIAGNOSTIC PROCEDURE Ð Mark detected items.
NVehicle speed sensor´A/T (Revolution sensor), AT-124.
NVehicle speed sensor´MTR, AT-129.
NThrottle position sensor, AT-132.
NShift solenoid valve A, AT-140.
NShift solenoid valve B, AT-146.
NOverrun clutch solenoid valve, AT-152.
NTorque converter clutch solenoid valve, AT-157.
NA/T fluid temperature sensor and TCM power source, AT-163.
NEngine speed signal, AT-170.
NLine pressure solenoid valve, AT-174.
NControl unit (RAM), control unit (ROM), AT-282.
NControl unit (EEP ROM), AT-284.
NPNP, overdrive control and throttle position switches, AT-326.
NBattery
NOthers
4-2. Check at idleAT-87
N1. O/D OFF Indicator Lamp Does Not Come On, AT-288.
N2. Engine Cannot Be Started In ªPº And ªNº Position, AT-291.
N3. In ªPº Position, Vehicle Moves Forward Or Backward When Pushed, AT-292.
N4. In ªNº Position, Vehicle Moves, AT-293.
N5. Large Shock. ªNº®ªRº Position, AT-295.
N6. Vehicle Does Not Creep Backward In ªRº Position, AT-297.
N7. Vehicle Does Not Creep Forward In ªDº, ª2º Or ª1º Position, AT-300.
TROUBLE DIAGNOSIS Ð
INTRODUCTION
EXCEPT FOR EURO-OBD
Introduction (Cont'd)
AT-69
4. 4-3. Cruise testAT-90
AT-93
Part-1
N8. Vehicle Cannot Be Started From D
1, AT-303.
N9. A/T Does Not Shift: D
1®D2Or Does Not Kickdown: D4®D2, AT-306.
N10. A/T Does Not Shift: D
2®D3, AT-309.
N11. A/T Does Not Shift: D
3®D4, AT-312.
N12. A/T Does Not Perform Lock-up, AT-315.
N13. A/T Does Not Hold Lock-up Condition, AT-317.
N14. Lock-up Is Not Released, AT-319.
N15. Engine Speed Does Not Return To Idle (Light Braking D
4®D3), AT-320.
Part-2AT-97
N16. Vehicle Does Not Start From D
1, AT-322.
N9. A/T Does Not Shift: D
1®D2Or Does Not Kickdown: D4®D2, AT-306.
N10. A/T Does Not Shift: D
2®D3, AT-309.
N11. A/T Does Not Shift: D
3®D4, AT-312.
Part-3AT-99
N17. A/T Does Not Shift: D
4®D3When Overdrive Control Switch ªONº®ªOFFº, AT-323
N15. Engine Speed Does Not Return To Idle (Engine Brake In D
3), AT-320.
N18. A/T Does Not Shift: D
3®22, When Selector Lever ªDº®ª2º Position, AT-324.
N15. Engine Speed Does Not Return To Idle (Engine Brake In 2
2), AT-320.
N19. A/T Does Not Shift: 2
2®11, When Selector Lever ª2º®ª1º Position, AT-325.
N20. Vehicle Does Not Decelerate By Engine Brake, AT-326.
N21. TCM Self-diagnosis Does Not Activate (PNP, Overdrive Control and Throttle Position Switches
Circuit Checks), AT-326.
NSELF-DIAGNOSTIC PROCEDURE Ð Mark detected items.
NVehicle speed sensor´A/T (Revolution sensor), AT-124.
NVehicle speed sensor´MTR, AT-129.
NThrottle position sensor, AT-132.
NShift solenoid valve A, AT-140.
NShift solenoid valve B, AT-146.
NOverrun clutch solenoid valve, AT-152.
NTorque converter clutch solenoid valve, AT-157.
NA/T fluid temperature sensor and TCM power source, AT-163.
NEngine speed signal, AT-170.
NLine pressure solenoid valve, AT-174.
NControl unit (RAM), control unit (ROM), AT-282.
NControl unit (EEP ROM), AT-284.
NPNP, overdrive control and throttle position switches, AT-326.
NBattery
NOthers
5.NFor self-diagnosis NG items, inspect each component. Repair or replace the damaged parts. AT-38
6.NPerform all ROAD TEST and re-mark required procedures. AT-83
7.NPerform the Diagnostic Procedures for all remaining items marked NG. Repair or replace the damaged
parts.
Refer to the Symptom Chart when you perform the procedures. (The chart also shows some other possible
symptoms and the component inspection orders.)AT-116
AT-103
8.NErase self-diagnosis code from TCM memories. AT-41
AT-47
TROUBLE DIAGNOSIS Ð
INTRODUCTION
EXCEPT FOR EURO-OBD
Introduction (Cont'd)
AT-70
Diagnostic Worksheet=NJAT0257S0102
1.NRead the Fail-safe and listen to customer complaints. AT-9
2.NCHECK A/T FLUIDAT-78
NLeakage (Follow specified procedure)
NFluid condition
NFluid level
3.NPerform STALL TEST and LINE PRESSURE TEST. AT-78, 82
NStall test Ð Mark possible damaged components/others.
NTorque converter one-way clutch
NReverse clutch
NForward clutch
NOverrun clutch
NForward one-way clutchNLow & reverse brake
NLow one-way clutch
NEngine
NLine pressure is low
NClutches and brakes except high clutch and
brake band are OK
NLine Pressure test Ð Suspected parts:
4.NPerform all ROAD TEST and mark required procedures. AT-83
4-1. Check before engine is started. AT-85
NSELF-DIAGNOSTIC PROCEDURE Ð Mark detected items.
NPNP switch, AT-181.
NA/T fluid temperature sensor, AT-187.
NVehicle speed sensor´A/T (Revolution sensor), AT-193.
NEngine speed signal, AT-198.
NTorque converter clutch solenoid valve, AT-231.
NLine pressure solenoid valve, AT-237.
NShift solenoid valve A, AT-244.
NShift solenoid valve B, AT-250.
NThrottle position sensor, AT-256.
NOverrun clutch solenoid valve, AT-265.
NPNP, overdrive control and throttle position switches, AT-326.
NA/T fluid temperature sensor and TCM power source, AT-271.
NVehicle speed sensor´MTR, AT-278.
NControl unit (RAM), control unit (ROM), AT-282.
NControl unit (EEP ROM), AT-284.
NBattery
NOthers
4-2. Check at idleAT-87
N1. O/D OFF Indicator Lamp Does Not Come On, AT-288.
N2. Engine Cannot Be Started In ªPº And ªNº Position, AT-291.
N3. In ªPº Position, Vehicle Moves Forward Or Backward When Pushed, AT-292.
N4. In ªNº Position, Vehicle Moves, AT-293.
N5. Large Shock. ªNº®ªRº Position, AT-295.
N6. Vehicle Does Not Creep Backward In ªRº Position, AT-297.
N7. Vehicle Does Not Creep Forward In ªDº, ª2º Or ª1º Position, AT-300.
TROUBLE DIAGNOSIS Ð INTRODUCTIONEURO-OBD
Introduction (Cont'd)
AT-74
4. 4-3. Cruise testAT-90
AT-93
Part-1
N8. Vehicle Cannot Be Started From D
1, AT-303.
N9. A/T Does Not Shift: D
1®D2Or Does Not Kickdown: D4®D2, AT-306.
N10. A/T Does Not Shift: D
2®D3, AT-309.
N11. A/T Does Not Shift: D
3®D4, AT-312.
N12. A/T Does Not Perform Lock-up, AT-315.
N13. A/T Does Not Hold Lock-up Condition, AT-317.
N14. Lock-up Is Not Released, AT-319.
N15. Engine Speed Does Not Return To Idle (Light Braking D
4®D3), AT-320.
Part-2AT-97
N16. Vehicle Does Not Start From D
1, AT-322.
N9. A/T Does Not Shift: D
1®D2Or Does Not Kickdown: D4®D2, AT-306.
N10. A/T Does Not Shift: D
2®D3, AT-309.
N11. A/T Does Not Shift: D
3®D4, AT-312.
Part-3AT-99
N17. A/T Does Not Shift: D
4®D3When Overdrive Control Switch ªONº®ªOFFº, AT-323
N15. Engine Speed Does Not Return To Idle (Engine Brake In D
3), AT-320.
N18. A/T Does Not Shift: D
3®22, When Selector Lever ªDº®ª2º Position, AT-324.
N15. Engine Speed Does Not Return To Idle (Engine Brake In 2
2), AT-320.
N19. A/T Does Not Shift: 2
2®11, When Selector Lever ª2º®ª1º Position, AT-325.
N20. Vehicle Does Not Decelerate By Engine Brake, AT-326.
NSELF-DIAGNOSTIC PROCEDURE Ð Mark detected items.
NPNP switch, AT-181.
NA/T fluid temperature sensor, AT-187.
NVehicle speed sensor´A/T (Revolution sensor), AT-193.
NEngine speed signal, AT-198.
NTorque converter clutch solenoid valve, AT-231.
NLine pressure solenoid valve, AT-237.
NShift solenoid valve A, AT-244.
NShift solenoid valve B, AT-250.
NThrottle position sensor, AT-256.
NOverrun clutch solenoid valve, AT-265.
NPNP, overdrive control and throttle position switches, AT-326.
NA/T fluid temperature sensor and TCM power source, AT-271.
NVehicle speed sensor´MTR, AT-278.
NControl unit (RAM), control unit (ROM), AT-282.
NControl unit (EEP ROM), AT-284.
NBattery
NOthers
5.NFor self-diagnosis NG items, inspect each component. Repair or replace the damaged parts. AT-53
6.NPerform all ROAD TEST and re-mark required procedures. AT-83
7.NPerform DTC CONFIRMATION PROCEDURE for following MIL indicating items and check out NG items.
Refer to EC-58, ªEmission-related Diagnostic Informationº.EC section
NDTC (P0731) A/T 1st gear function, AT-202.
NDTC (P0732) A/T 2nd gear function, AT-209.
NDTC (P0733) A/T 3rd gear function, AT-215.
NDTC (P0734) A/T 4th gear function, AT-221.
8.NPerform the Diagnostic Procedures for all remaining items marked NG. Repair or replace the damaged
parts.
Refer to the Symptom Chart when you perform the procedures. (The chart also shows some other possible
symptoms and the component inspection orders.)AT-103
AT-116
9.NErase DTC from TCM and ECM memories. AT-50
TROUBLE DIAGNOSIS Ð INTRODUCTIONEURO-OBD
Introduction (Cont'd)
AT-75
JUDGEMENT OF LINE PRESSURE TESTNJAT0027S03
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
position.+Fluid pressure leakage between manual valve and particular clutch
+For example, line pressure is:
þ Low in ªRº and ª1º positions, but
þ Normal in ªDº and ª2º positions.
Therefore, fluid leakage exists at or around low and reverse brake circuit.
Refer to ªCLUTCH AND BAND CHARTº, AT-21.
Line pressure is high.+Maladjustment of throttle position sensor
+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.+Maladjustment of throttle position sensor
+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
Road TestNJAT0028DESCRIPTIONNJAT0028S01+The purpose of the test is to determine overall performance of
A/T and analyze causes of problems.
+The road test consists of the following three parts:
1. Check before engine is started
2. Check at idle
3. Cruise test
SAT496G
+Before road test, familiarize yourself with all test procedures
and items to check.
+Conduct tests on all items until specified symptom is found.
Troubleshoot items which check out No Good after road test.
Refer to the following items.
ON BOARD DIAGNOSITC
SYSTEM DESCRIPTIONTROUBLE DIAGNOSES FOR
SYMPTOMS
General and
Except for
Euro-OBDAT-37 - AT-47 AT-286 and AT-288 - AT-326
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Line Pressure Test (Cont'd)
AT-83
Symptom Condition Diagnostic ItemReference Page
Except for
Euro-OBDEURO-OBD
Vehicle braked when shifting into
ªRº position.ON vehicle1. Fluid level AT-78¬
2. Control cable adjustment AT-344¬
3. Line pressure test AT-82¬
4. Line pressure solenoid valve AT-174 AT-237
5. Control valve assembly AT-343¬
OFF vehicle6. High clutch AT-394¬
7. Brake band AT-419¬
8. Forward clutch AT-399¬
9. Overrun clutch AT-399¬
Sharp shock in shifting from ªNº to
ªDº position.ON vehicle1. Engine idling rpmEC-41, ªIdle
Speed and
Ignition Tim-
ingºEC-41, ªIdle
Speed and
Ignition Tim-
ingº
2. Throttle position sensor (Adjustment)EC-168,
ªDTC P0120
THROTTLE
POSITION
SENSORºEC-168,
ªDTC P0120
THROTTLE
POSITION
SENSORº
3. Line pressure test AT-82¬
4. A/T fluid temperature sensor AT-163 AT-187
5. Engine speed signal AT-170 AT-198
6. Line pressure solenoid valve AT-174 AT-237
7. Control valve assembly AT-343¬
8. Accumulator N-D AT-343¬
OFF vehicle 9. Forward clutch AT-399¬
Vehicle will not run in ªDº and ª2º
positions (but runs in ª1º and ªRº
positions).ON vehicle 1. Control cable adjustment AT-344¬
OFF vehicle 2. Low one-way clutch AT-350 AT-350
Vehicle will not run in ªDº, ª1º, ª2º
positions (but runs in ªRº position).
Clutch slips. Very poor accelera-
tion.
AT-300ON vehicle1. Fluid level AT-78¬
2. Line pressure test AT-82¬
3. Line pressure solenoid valve AT-174 AT-237
4. Control valve assembly AT-343¬
5. Accumulator N-D AT-343¬
OFF vehicle6. Reverse clutch AT-390¬
7. High clutch AT-394¬
8. Forward clutch AT-399¬
9. Forward one-way clutch AT-410¬
10. Low one-way clutch AT-350 AT-350
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTION
Symptom Chart (Cont'd)
AT-104
Symptom Condition Diagnostic ItemReference Page
Except for
Euro-OBDEURO-OBD
Clutches or brakes slip somewhat
in starting.ON vehicle1. Fluid level AT-78¬
2. Control cable adjustment AT-344¬
3. Throttle position sensor (Adjustment)EC-168,
ªDTC P0120
THROTTLE
POSITION
SENSORºEC-168,
ªDTC P0120
THROTTLE
POSITION
SENSORº
4. Line pressure test AT-82¬
5. Line pressure solenoid valve AT-174 AT-237
6. Control valve assembly AT-343¬
7. Accumulator N-D AT-343¬
OFF vehicle8. Forward clutch AT-399¬
9. Reverse clutch AT-390¬
10. Low & reverse brake AT-406¬
11. Oil pump AT-371¬
12. Torque converter AT-354¬
Excessive creep. ON vehicle 1. Engine idling rpmEC-41, ªIdle
Speed and
Ignition Tim-
ingºEC-41, ªIdle
Speed and
Ignition Tim-
ingº
No creep at all.
AT-297 and AT-300ON vehicle1. Fluid level AT-78¬
2. Line pressure test AT-82¬
3. Control valve assembly AT-343¬
OFF vehicle4. Forward clutch AT-399¬
5. Oil pump AT-371¬
6. Torque converter AT-354¬
Failure to change gear from ªD
1º
to ªD
2º.ON vehicle1. PNP switch adjustment AT-344¬
2. Control cable adjustment AT-344¬
3. Shift solenoid valve A AT-140 AT-244
4. Control valve assembly AT-343¬
5. Vehicle speed sensor´A/T (Revolution
sensor) and vehicle speed sensor´MTRAT-124,
AT-129AT-193,
AT-278
OFF vehicle 6. Brake band AT-419¬
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTION
Symptom Chart (Cont'd)
AT-105