TOYOTA SUPRA 1995 Service Repair Manual

±Memo±
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±55

STANDARD VALUE OF ECM TERMINAL
* A = (E10), B = (E9) 
 Terminals
 
 Symbols
 
 Wiring
Color 
 Condition
 
 Standard
Value
 B76 ± B69 NSW±E1 B±WeBR IG ON Shift Lever; P or N position Below 3 V
 B76 ± B69 NSW ± E1 B±W eBR IG ON Shift Lever; Other than P or N position 9 ± 14 V
 B3 ± B23 SP2± ± SP2+ G eR IG OFF 560 ± 680

IG OFF10 ± 16
 B10 ± B69 S1 ± E1 W±R eBR Vehicle driving in 2nd gear position 9 ± 14
    IG ON 9 ± 14
    IG OFF 10 ± 16

 B9 ± B69 S2 ± E1 RL eBR Vehicle driving in 2nd or 3rd position 9 ± 14

    IG ON  Below 1.5 V
 B43 ± B65 VTA1±E2 YeBR±B IG ON Accel. pedal is not depressed Below 0.8 V
 B43 ± B65 VTA1 ± E2 Y eBR±B IG ON Accel. pedal is fully depressed 3.2 ± 4.9 V
B64 ± B65IDL1 ± E2ReBR±BIG ONAccel. pedal is not depressedBelow 3 V B64 ± B65 IDL1 ± E2 R eBR±B IG ON Accel. pedal is depressed 9 ± 14 V 
 A2 ± B65
 
 SP1 ± E2
 
 P eBR±B
 
 Ignition switch ON
Turn the rear wheel slowly 
 Repeat 0±8V
or above
 
A3 ± B69
 
KD±E1
 
YeBR
 
IG ON
 Kick±down SW; OFF
(Accel. pedal is not depressed) 9 ± 14 V
 
 
A3 ± B69 
 
KD ± E1 
 
Y eBR 
 
IG ON 
 Kick±down SW; ON
(Accel. pedal is fully depressed) 
 Below 3 V
 A9 ± B69 2±E1 LG±ReBR IG ON Shift Position; 2 position 7.5 ± 14 V
 A9 ± B69 2 ± E1 LG±R eBR IG ON Shift Position; Other than 2 position Below 1.5 V
 A10 ± B69 L±E1 G±BeBR IG ON Shift Position; L position 7.5 ± 14 V

A10 ± B69

L ± E1

G±B eBR

IG ON
Shift Position; Other than L positionBelow 1.5 V A12 ± B69 OD1 ± E1 BR±B eBR Ignition switch ON 4.5 ± 5.5 V 
A18 ± B69
 
M±E1
 
G±YeBR
 
IG ON
 Pattern select SW: MANU 7.5 ± 14 V
 A18 ± B69 M ± E1 G±Y eBR IG ON Pattern select SW: NORM Below 1.5 V
 A28 ± B69 OD2±E1 V±GeBR IG ON O/D main SW; ON 7.5 ± 14 V
 A28 ± B69 OD2 ± E1 V±G eBR IG ON O/D main SW; OFF Below 3 V
 B24 ± B65 OIL ± E2 BR±B eO A/T fluid temperature 110°C (230°F) Below 1 V
AT1±56± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

MATRIX CHART OF PROBLEM SYMPTOMS
If a normal code is displayed during the diagnostic trouble code check but the trouble still occurs, check
the circuits for each symptom in the order given in the charts on the following pages and proceed to the
page given for troubleshooting.
The Matrix Chart is divided into 3 chapters.
Chapter 1: Electronic Circuit Matrix Chart
Chapter 2: On±vehicle Repair Matrix Chart
Chapter 3: Off±vehicle Repair Matrix Chart
When troubleshooting, check Chapter 1 first. If instructions are given in Chapter 1 to proceed to Chapter
2 or 3, proceed as instructed.
1. If the instruction ºProceed to next circuit inspection shown on matrix chartº is given in the flow chart for each
circuit, proceed to the circuit with the next highest number in the table to continue the check.
2. If the trouble still occurs even though there are no abnormalities in any of the other circuits, then check or
replace the ECM.
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±57

Chapter 1. Electronic Circuit
AT1±66AT1±69AT1±72AT1±75AT1±77AT1±81AT1±79
No.1 Vehicle speedsensor circuitNo.2 Vehicle speed
sensor circuitNo.1, No.2 Sole-
noid circuitkick±down switch
circuitThrottle position
sensor circuitSL Solenoid
circuitPark/neutral posi-
tion switch circuit
See Page
Suspect Area
Symptom
Vehicle does not move in any forward position and reverse position
Vehicle does not move in particular position or positions
No up±shift
No down±shift
No lock±up
No lock±up off
Shift point too high or too low
Up±shifts to 2nd while in L positionUp±shifts to 3rd while in L position
Up±shifts to O/D from 3rd while O/D switch is OFF
Up±shifts to O/D from 3rd while engine is cold
Harsh engagement
Slip or Shudder
Poor acceleration
No kick±down
No engine braking
No pattern select*
Large shift shock or engine stalls when starting off or stopping.
Any particular position
Forward and reverse
Any driving position
Lock±up
N " D
1st " 2nd
2nd " 3rd
3rd " O/D
O/D " 3rd
3rd " 2nd
2nd " 1st
* The automatic transmission is not shifted into the manual mode when the automatic transmission
fluid temperature is too high. AT1±58
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

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

Chapter 2. On±Vehicle Repair
( : A340E, A340F, A340H AUTOMATIC TRANSMISSION Repair Manual Pub. No. RM391U)
AT1±43AT1±43
See Page
Suspect Area
Symptom
Vehicle does not move in any forward position and reverse position
Vehicle does not move in particular position or positions
No up±shift
No down±shift
No lock±up or No lock±up off
Vehicle does not move in particular position or positions
(except R position)
Harsh engagement
Slip or Shudder
No kick±down
No engine braking
N " D
1st " 2nd
2nd " 3rd
3rd " O/D
O/D " 3rd
3rd " 2nd
2nd " 1st
N " D
N " R
1st " 2nd (2 position)
2nd " 3rd " O/D
2nd " 3rd
3rd " O/D
O/D " 3rd
Lock±up
1st " 2nd (D position)
1st " 2nd "
3rd " O/D
2nd
1st
Particular position
Forward and Reverse
Throttle cable1±2 shift valve2±3 shift valveThrottle valveManual valveParking lock pawlOil strainerTransmission
control rod
AT1±60± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

AT1±62
3±4 shift valveLow coast
modulator valveB2 accumulator
C2 accumulatorCut±back valveLock±up relay valvePrimary regulator
valveAccumulatorcontrol valve2nd coast
modulator valvePressure relief
valveOFF±Vehicle repair
matrix chartB0 accumulatorC0 accumulator
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±61

Chapter 3. Off±Vehicle Repair
(: A340E, A340F, A340H AUTOMATIC TRANSMISSION Repair Manual Pub. No. RM391U)
AT1±26
See Page
Suspect Area
Symptom
Vehicle does not move in any forward position and reverse position
Vehicle does not move in R position
No up±shift
No down±shift
Harsh engagement
Slip or Shudder
1st " 2nd
2nd " 3rd
3rd " O/D
O/D " 3rd
L position
2nd " 1st
D, 2 and L positions
D and 2 positions
2 position
Vehicle does not
move in:
No lock±up or No lock±up off
N " D
N " R
2nd " 3rd
3rd " O/D
Lock±up
Forward & Reverse (After warm±up)
Forward & Reverse (Just after engine starts)
R position
No engine braking
2nd
1st
3rd
2nd
1st
1st ~ 3rd
O/D
O/D
All position
Other than O/D
1st and 2nd
1st and R position
R position
Other than 2ndPoor acceleration
Engine stalls when starting off or stopping
O/D one±wayclutch (F
o)
O/D brake (B
o)
Torque converter
clutchO/D Planetary gear
unitO/D
direct clutch
(co)
1st reverse
brake (B
3)
AT1±62± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

2nd coast brake(B1)
Direct clutch (C
2)
No.2 one±way
clutch (F
2)
Forward clutch
(C1)
Front and rear
planetary gear unit2nd brake (B
2)
No.1 one±way
clutch (F
1)
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±63

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