1995 TOYOTA SUPRA transmission fluid

AT1±83AT1±85AT1±88AT1±91AT1±64EG±312AT1±56AT1±60AT1±62
Stop light switch
circuitPattern select switch
circuitO/D switch O/D OFF
indicator light circuitECMA/T fluid temp.
sensor circuitO/D cancel signal
circuitEngine coolant
temp. switch circuitOFF±Vehicle repairmatrix chartOn±Vehicle repairmatrix chart
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±59

CIRCUIT INSPECTION
DTC 38 A T Fluid Temperature Sensor Circuit
CIRCUIT DESCRIPTION
The fluid temp. sensor converts fluid temp. into resistance values which is input into the ECM.
 DTC No. Diagnostic Trouble Code Detection Condition Trouble Area
 
 
 
 
 
38
 
 
 
 
 
Either (a) or (b) are detected for 0.5 sec. or more
(a) Temp. sensor resistance less than 79

(b) After the engine has been operating for 15 minutes
or more, the resistance at the temp. sensor is more than
156 k
 
 
 
 
 

Harness or connector between A/T
fluid temp. sensor and ECM

A/T fluid temp. sensor

ECM
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±64

INSPECTION PROCEDURE
Check sensor resistance
Remove A/T fluid temp. sensor.
Measure resistance between terminals of A/T fluid
temp. sensor at 20°C (68°F) and 110°C (230°F).
Resistance:
20°C (68°F) Approx. 12.08 k

110°C (230°F) Approx. 0.78 k

Replace A/T fluid temp. sensor.
Repair or replace harness or connector.
Check harness and connector between battery and A/T fluid temp. sensor
A/T fluid temp. sensor and ECM. (See page IN±30).
Check A/T fluid temp. sensor.
Check and replace ECM. AT1±65
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

Pattern Select Switch Circuit
CIRCUIT DESCRIPTION
The ECM memory contains the shift programs for the NORMAL and MANUAL patterns, 2 position, and L posi-
tion and the lock±up patterns. Following the programs corresponding to the signals from the pattern select
switch, the park/neutral position switch and other various sensors the ECM switches the solenoid valves ON
and OFF, thereby controlling the transmission gear change and the lock±up clutch operation.
WIRING DIAGRAM
INSPECTION PROCEDURE
Check A/T fluid temp. sensor. (See page AT1±64).
Replace A/T fluid temp. sensor.
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±85

Turn ignition siwtch ON.
Check ªMANUº mode indicator light when pat-
tern select switch is pushed in to ON.
Check if A/T fluid is too hot.
Pattern select switch
Connect the Check Harness A to the ECM
(See page EG±404).
Turn igntion switcn ON.
Check voltage between terminal M of ECM connector and body ground.
Proceed to next circuit inspection shown on
matrix chart. (See page AT1±58)
Voltage
MANU7.5 ± 14 V
NORMBelow 1.5 V
Wait until the A/T fluid temp. is reduced.
The ECM uses the Normal pattern signal if the
Manual signal is not input.
Measure voltage between the terminal M of ECM
connector and body ground when the pattern se-
lect switch is set to the MANU (MANUAL) position
and NORM (NORMAL) position.
ºMANUº mode indicator light comes on and stays
on.
If the A/T fluid temp. becomes too hot, the
ªMANUº mode indicator light flashes for several
seconds and goes off. The driving mode then
automatically changes from MANU mode to the
NORM mode. AT1±86
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

TORQUE SPECIFICATIONS
 Part tightened NVm kgfVcm ftVlbf
 Engine block X Transmission 14 mm 37 380 27 
 17 mm
 
 72
 
 730
 
 53
 Rear mounting X Body 25 260 19
 Extension housing X Transmission case 36 370 27
 Valve body X Transmission case 10 100 7 
 Oil strainer
 
 10
 
 100
 
 7
 Oil pan 7.4 75 65 in.Vlbf
 No.1 vehicle speed sensor 16 160 12
 No.2 vehicle speed sensor 5.4 55 48 in.Vlbf 
 Solenoid wiring stopper plate
 
 5.4
 
 55
 
 48 in.Vlbf
 Rear center floor crossmember brace X Body 13 130 9
 Propeller shaft X Differential 79 805 58
 Manual shift linkage X Control shaft lever 13 130 9 Center support bearing X Body 49 500 36 
 Throttle cable X Transmission case
 
 5.4
 
 55
 
 48 in.Vlbf
 Cooler pipe union nut 34 350 25
 Drive plate X Crankshaft 74 750 54
 Torque converter clutch X Drive plate 33 340 25 
 Control shaft lever X Park/Neutral position switch
 
 16
 
 160
 
 12
 A/T fluid temp. sensor 15 150 11
 Drain plug 20 205 15
 Solenoid valve X Valve body 10 100 7 
 Parking lock pawl bracket
 
 7.4
 
 75
 
 65 in.Vlbf
 Transmission mounting bracket X Extension housing 25 250 18
 Heat insulator X Body 5.4 55 48 in.Vlbf
 Starter 37 380 27
AT1±98± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONSERVICE SPECIFICATIONS

HYDRAULIC CONTROL SYSTEM
The hydraulic control system is composed of an oil pump, valve body, solenoid valves, accumulators,
clutches and brakes, as well as the fluid passages which connect all of these components. Based on the
hydraulic pressure created by the oil pump, the hydraulic control system governs the hydraulic pressure
acting on the torque converter clutch, clutches and brakes in accordance with the vehicle driving condi-
tions.
There are five solenoid valves on the valve body.
The No.1 and No.2 solenoid valves are turned on and off by signals from the ECM to control the shift valves,
and change the gear shift position.
The No.3 solenoid valve is operated by signals from the ECM to engage or disengage the lock±up clutch
of the torque converter clutch.
The No.4 solenoid valve is operated by signals from the ECM to control the engagement speed and reduce
gear shift shock.
The No.5 solenoid valve is operated by signals from the ECM to regulate the line pressure to throttle pres-
sure.
HYDRAULIC CONTROL SYSTEM
VALVE BODY
OIL PUMP
ECMSOLENOID VALVES
CLUTCHES & BRAKES
Hydr. pressure control
Fluid passage switchingPlanetary gear sets
Torque Converter Clutch
AT2±6± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONOPERATION

ELECTRONIC CONTROL SYSTEM
The electronic control system for the A340E automatic transmission provides extremely precise control of
the gear shift timing and lock±up timing in response to driving conditions as sensed by various sensors
located throughout the vehicle and in response to the engine's running condition.
At the same time, the ECM control reduces vehicle squat when the vehicle starts out and gear shift shock.
The electronic control system is also equipped with a self diagnosis system which diagnoses malfunctions
for the vehicle to continue functioning when a malfunction occurs.
CONSTRUCTION
The electronic control system can be broadly divided onto three groups; the sensors, ECM and actuators.
No. 1 Vehicle Speed Sensor
No. 2 Vehicle Speed Sensor
Crankshaft Position Sensor
Camshaft Position Sensor No.1, No.2
Park/Neutral Position Switch

Neutral Start Signal

Shift lever Position Signal

Idling Signal

Throttle Position Signal
Main (Sub) Ð throttle Position Sensor
Engine Coolant temp. Sensor
A/T Fluid Temp. Sensor
O/D Main Switch
Cruise Control ECU
Kick±Down Switch
Stop Light Switch
Pattern Select Switch
SENSORSECMACTUATORS
No.1 Solenoid Valve
No.2 Solenoid Valve
No.3 Solenoid Valve
No.4 Solenoid Valve
No.5 Solenoid Valve
Engine Torque Control (ESA)
Igniters
Ignition Coils
Distributors
Spark Plugs
O/D OFF Indicator Light
(Diagnostic Trouble Code
Display)
TRAC ECU
O/D Direct Clutch Speed Sensor
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONOPERATIONAT2±7