1995 TOYOTA SUPRA clutch

PROBLEM SYMPTOM CONFIRMATION
Taking into consideration the results of the customer problem analysis, try to reproduce the symptoms of
the trouble. If the problem is that the transmission does not up±shift, does not down±shift, or the shift point
is too high or too low, conduct the following road test to confirm the automatic shift schedule and simulate
the problem symptoms.
ROAD TEST
NOTICE: Do the test at normal A/T fluid operating temp.
50±805C (122±1765F).
1. D POSITION TEST (NORM PATTERN)
Shift into the D position and keep the accelerator pedal
constant at the full throttle valve opening position, and check
the following points:
(a) Check up±shift operation.
Check that 1±2, 2±3 and 3±O/D up±shift takes place, at the
shift point shown in the automatic shift schedule.
(See page AT2±116)
HINT:
(1) O/D Gear Up±shift Prohibition Control.
wCoolant temp. is 605C (1405F) or less.
wIf there is a 10 km/h (6 mph) difference between the set
cruise control speed and vehicle speed.
wO/D main switch is pushed ON.
`(During O/D OFF, indicator light lights up.)
(2) O/D Gear Lock±up Prohibition Control.
wBrake pedal is depressed.
wCoolant temp. is 605C (1405F) or less.
(b) Check for shift shock and slip.
Check for shock and slip at the 1±2, 2±3, and 3±O/ D up±
shifts.
(c) Check for abnormal noise and vibration.
Run at the D position lock±up or O/D gear and check for ab-
normal noise and vibration.
HINT: The check for the cause of abnormal noise and vibra-
tion must be performed very thoroughly as it could also be
due to loss of balance in the, torque converter clutch, etc.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±37

(c) Check for abnormal noise and vibration.
Run at the D position lock±up or O/D gear and check for ab-
normal noise and vibration.
HINT: The check for the cause of abnormal noise and vibra-
tion must be made with extreme care as it could also be due
to loss of balance in the propeller shaft, differential, torque
converter clutch, etc.
(d) Check kick±down operation.
While running in the D position, 2nd, 3rd and O/D gears,
check to see that the possible kick±down vehicle speed limits
for 3
" 2 and O/D " 3 kick±downs conform to those indicated
on the automatic shift schedule.
(See page AT2±116)
(e) Check for abnormal shock slip at kick±down.
(f) Check the lock±up mechanism.
(1) Drive in D position, O/D gear, at a steady speed (lock±up
ON) of about 195 km/h (121 mph).
(2) Lightly depress the accelerator pedal and check that the
engine RPM does not change abruptly.
If there is big jump in the engine RPM there is no lock ±up.
3. 2 POSITION TEST (NORM PATTERN)
Shift into the 2 position and, while driving with the accelerator
pedal held constantly at the full throttle valve opening posi-
tion, check on the following points:
(a) Check up±shift operation.
Check to see that the 1
" 2 up±shift takes place and that the
shift point conforms to the automatic shift schedule.
(See page AT2±116)
HINT: There is no O/D up±shift and lock±up in the 2 position.
(b) Check engine braking.
While running in the 2 position and 2nd gear, release the ac-
celerator pedal and check the engine braking effect.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±39

EVALUATION
 Problem Possible cause 
 
 (a) Stall speed low in D and Rpositions
 Engine output may be insufficient.
 Stator one±way clutch is operating properly
HINT: 
 
(a) Stall speed low in D and R positions. HINT:
If more than 600 rpm below the specified value, the
torque converter clutch could be faulty.
 
 (b) Stall speed high in Dposition
 Line pressure too low.
 Forward clutch slipping
 
 
(b) Stall speed high in D position Forward clutch sli ing
 No.2 one±way clutch not operating properly
 O/D one±way clutch not operating properly
 
 (c) Stall speed high in Rposition
 Line pressure too low
 Direct clutch slipping
 
 
(c) Stall speed high in R position. Direct clutch sli ing
 First and reverse brake slipping
 O/D clutch slipping
 
(d) Stall speed high in D and Rpositions
 Line pressure too low
Improper fluid level (d) Stall speed high in D and R positions. Improper fluid level
 O/D one±way clutch not operating properly
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±45

TIME LAG TEST
When the shift lever is shifted while the engine is idling, there will be a certain time lapse or lag before the
shock can be felt. This is used for checking the condition of the O/D direct clutch, forward clutch, direct
clutch, and first and reverse brake.
NOTICE:
wDo the test at normal operating fluid temp. 50±805C (122±1765F).
wBe sure to allow 1 minute interval between tests.
wTake 3 measurements and take the average value.
MEASURE TIME LAG
(a) Fully apply the parking brake
(b) Start the engine and check idle speed.
Idle speed:
650+50 rpm (In N position and air conditioner OFF)
(c) Shift the shift lever from N to D position. Using a stop watch, measure the time it takes from shifting the
lever until the shock is felt.
In same manner, measure the time lag for N " R.
Time lag:
N
"D Less than 1.2 seconds
N
"R Less than 1.5 seconds
AT2±46± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

EVALUATION
If N "D or N "R time lag is longer than specified:
 Problem Possible cause 
 N"D time lag is longer
 Line pressure too low
Forward clutch worn  N"D time lag is longer Forward clutch worn
 O/D one±way clutch not operating properly
 
 
N"R time lag is longer
 Line pressure too low
 Direct clutch worn
 
 
N"R time lag is longer Direct clutch worn
 First and reverse brake worn
 O/D clutch worn
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±47

SPECIFIED LINE PRESSURE
Line pressure:
 Condition D position kPa (kgf/cm2 psi) R position kPa (kgf/cm2, psi) Idling471±530 (4 8±5 4 68±77)686±785 (7 0±8 0 100±114)Idling471±530 (4.8±5.4, 68±77)686±785 (7.0±8.0, 100±114) 
Stall1 334±1 470 (13 6±15 0 193±213)1 697±2 030 (17 3±20 7 246±294) Stall1,334±1,470 (13.6±15.0, 193±213)1,697±2,030 (17.3±20.7, 246±294)
If the measured pressures are not up to specified values, check the No.5 solenoid valve and retest.
EVALUATION 


Problem
 
 Possible cause
 
If the measured values at allpositions are higher

Throttle cable out of adjustment

Throttle valve defective If the measured values at all positions are higher.
Throttle valve defective

Regulator valve defective
 


If the measured values at allpositions are lower

Throttle cable out of adjustment

Throttle valve defective

Regulator valve defective 


If the measured values at all positions are lower.
Regulator valve defective

Oil pump defective

O/D direct clutch defective
 
Ifpressure is low in the Dposition only
D position circuit fluid leakage
 If pressure is low in the D position only.g

Forward clutch defective
 


Ifpressure is low in the Rposition only

R position circuit fluid leakage

Direct clutch defective
 
If pressure is low in the R position only.
Direct clutch defective

First and reverse brake defective
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±49

DTC.
No.Blinking
PatternCircuitDiagnostic Trouble Code Detection Condition
67
77
89
O/D direct
clutch speed
sensor
No.5 solenoid
circuit
TRAC ECU
circuit
All conditions below are detected for 4 secs. or more:
(2 trip detection logic)*3
(a) Gear change not being performed.
(b) Gear position: 1st, 2nd or 3rd
(c) T/M input shaft rpm: Less than 300 rpm
(d) T/M output shaft rpm: 1000 rpm or more
Any of condition below are detected:
(2 trip detection logic)*3
(a) SLT
± terminal: 0 V or 5 V for 1 sec. or more.
All conditions below are detected for 5 secs. or more:
(a) No.1 vehicle speed sensor: 9 km/h (5.6 mph) or more
(b) Mirror check of TRAC ECU input signal is abnormal.
(c) TRAC ECU input signal does not inform to ECM.
(d) TRAC ECU input signal order is abnormal.
AT2±56± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

 Trouble Area O/D OFF Indicator
Light *1Blinks
 Memory *2 See
Page Trouble Area Light *1 Blinks Memory  Page
 
 
 
 
 

Harness or connector between O/D direct clutch speed sensor
and ECM

O/D direct clutch speed sensor

ECM
 
 
 
 
 

 
 
 
 
 

 
 
 
 
 
AT2±89
 
 
 
 
 
 

Harness or connector between No.5 solenoid valve and

ECM

No.5 solenoid valve

ECM
 
 
 
 
 
 

 
 
 
 
 
 

 
 
 
 
 
 
AT2±92
 
 
 
 
 
 

Harness or connector between TRAC ECU and ECM.

TRAC ECU
 
 
 
 
 
 

 
 
 
 
 
 

 
 
 
 
 
 
AT2±95
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