check engine light TOYOTA SUPRA 1995 Service User Guide

(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 indi-
cated on the automatic shift schedule.
(See page AT1±96)
(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 172 km/h (107 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 AT1±96)
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.
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±39

5. INSPECT AND ADJUST THROTTLE CABLE
(a) Check that the throttle valve is fully closed.
(b) Check that the inner cable is not slack.
(c) Measure the distance between the outer cable end and
stopper on the cable.
Standard distance:
0±1 mm (0±0.04 in.)
If the distance is not standard, adjust the cable by the adjust-
ing nuts.
6. INSPECT AND ADJUST SHIFT LEVER POSITION
When shifting the shift lever from the N position to other posi-
tions, check that the lever can be shifted smoothly and accu-
rately to each position and that the position indicator correctly
indicates the position.
If the indicator is not aligned with the correct position, carry
out the following adjustment procedures:
(a) Loosen the nut on the control shaft lever.
(b) Push the control shaft lever fully rearward.
(c) Return the control shaft lever 2 notches to N position.
(d) Set the shift lever to N position.
(e) While holding the shift lever lightly toward the R position side,
tighten the shift lever nut.
(f) Start the engine and make sure that the vehicle moves
forward when shifting the lever from the N to D position and
reverses when shifting it to the R position.
7. INSPECT AND ADJUST PARK/NEUTRAL POSITION
SWITCH
Check that the engine can be started with the shift lever only
in the N or P position, but not in other positions.
If not as started above, carry out these adjustment proce-
dures:
(a) Loosen the park/neutral position switch bolt and set the shift
lever to the N position.
(b) Align the groove and neutral basic line.
(c) Hold in position and tighten the bolt.
Torque: 13 NVm (130 kgfVcm, 9 ftVlbf)
For continuity inspection of the park/neutral position switch,
see page AT1±81.
8. INSPECT IDLE SPEED
Idle speed:
700 + 50 rpm
(In N position and air conditioner OFF)
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±43

DTC
No.Blinking
PatternCircuitDiagnostic Trouble Code Detection Condition
38
42
Either (a) or (b) are detected for 0.5 sec. or more.
(a) Temperature sensor resistance less than 79 
(b) After the engine has been operating for 15 minutes or more,
the resistance at the temperature sensor is more than 156 k
All conditions below are detected 500 times or more continuously.
(2 trip detection logic) *3
(a) No No. 1 vehicle speed sensor signal in 16 pulses of No. 2
vehicle speed sensor signal.
(b) Vehicle speed: 9 km/h (5.6 mph) or more for 4 secs. or more.
(c) Park/neutral position switch: OFF (Other than P or N position)
A/T fluid
temp.
sensor
No. 1 vehicle
speed sensor
No. 2 vehicle
speed sensor
All conditions below are detected 500 times or more continuously.
(2 trip detection logic) *3
(a) No No. 2 vehicle speed sensor signal in 4 pulses of No. 1
vehicle speed sensor signal.
(b) Vehicle speed: 9 km/h (5.6 mph) or more for 4 secs. or more.
(c) Park/neutral position switch: OFF (Other than P or N position)
No. 1
solenoid
valve
(1) Solenoid resistance of 8 or less is detected (*) 8 times or
more when No. 1 solenoid is energized.
(2) Solenoid resistance of 100 k or more is detected (*) 8 times
or more when No. 1 solenoid is not energized.
(*) If the above failures are detected less than 8 times, the ECM
memorizes the malfunction code but the O/D OFF indicator
light does not blink.
No. 2
solenoid
valve
(1) Solenoid resistance of 8 or less is detected (*) 8 times or
more when No. 2 solenoid is energized.
(2) Solenoid resistance of 100 k or more is detected (*) 8 times
or more when No. 2 solenoid is not energized.
(*) If the above failures are detected less than 8 times, the ECM
memorizes the malfunction code but the O/D OFF indicator
light does not blink.
Lock±up
solenoid
valve
(a) Solenoid resistance is 8 or lower (short circuit) when
solenoid energized.
(b) Solenoid resistance is 100 k or higher (open circuit) when
solenoid is not energized.
(*) ECM memorizes diag. trouble code 64 if above (a) or (b)
condition is detected once or more, but ECM does not start
O/D OFF indicator light blinking.
61
62
63
64
DIAGNOSTIC TROUBLE CODE CHART
If a diagnostic trouble code is displayed during the diagnostic trouble code check, check the circuit listed
for that code in the table below and proceed to the page given. AT1±52
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

See
Stop Light Switch Circuit
CIRCUIT DESCRIPTION
The purpose of this circuit is to prevent the engine from stalling, while driving in lock±up condition, when brakes
are suddenly applied.
When the brake pedal is operated, this switch sends a signal to ECM. Then the ECM cancels operation of the
lock±up clutch while braking is in progress.
WIRING DIAGRAM
INSPECTION PROCEDURE
Check operation of stop light.
Check and repair stop light circuit.
Check if the stop lights go on and off normally when the brake pedal is depressed and
released.
± AT340E (2JZ±GE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT1±83

DIAGNOSIS SYSTEM
The automatic transmission has built±in self±diagnostic
functions. If a malfunction occurs in the system, the ECM
stores the diagnostic trouble code in memory and the O/D
OFF (Overdrive OFF) indicator light blinks to inform the driv-
er. The diagnostic trouble code stored in memory can be read
out by the following procedure.
O/D OFF INDICATOR LIGHT INSPECTION
1. Turn the ignition switch ON.
2. Check if the O/D OFF indicator light lights up when the O/D
main switch is pushed out to OFF and goes off when the O/D
main switch is pushed in to ON.
HINT: If the O/D OFF indicator light does not light up or stay
on all the time, carry out the check for ºO/D OFF Indicator
Light Circuitº on page AT2±108.
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn the ignition switch ON, but do not start the engine.
2. Push in the O/D main switch to ON.
HINT: Warning and diagnostic trouble codes can be read only
when the O/D main switch is ON. If it is OFF, the O/D OFF indi-
cator light up will light continuously and will not blink.
3. Using SST, connect terminals TE1 and E1 of the DLC 1 or
DLC2.
SST 09843±18020
4. Read the diagnostic trouble code indicated by the number of
times the O/D OFF indicator light blinks
(See next page).
HINT: If the system is operating normally, the light will blink
2 times per second. AT2±34
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

CHECK TERMINAL TT OUTPUT
VOLTAGE
When a voltmeter is connected to the DLC2, the following
items can be checked.
1. Throttle position sensor signal
2. Brake signal
3. Shift position signal
1. VOLTMETER CONNECTION
Connect the positive (+) probe of the voltmeter to terminal TT
and the negative (±) probe to terminal E1 of the DLC2.
HINT: If a voltmeter with small internal resistance is used, the
correct voltage will not be indicated, so use a voltmeter with
an internal resistance of at least 10 k
/V.
2. TURN IGNITION SWITCH TO ON (DO NOT START THE
ENGINE)
3. CHECK THROTTLE POSITION SENSOR SIGNAL
Check if the voltage changes from approx. 0 V to approx. 8
V when the accelerator pedal is gradually depressed from the
fully closed position.
4. CHECK BRAKE SIGNAL (LOCK±UP CUT SIGNAL)
(a) Open the throttle valve fully to apply approx. 8 V to terminal
TT.
(b) In this condition, check terminal TT voltage when the brake
pedal is depressed and released.
TT terminal voltage:
0 V (When brake pedal is depressed)
8 V (When brake pedal is released)
5. START ENGINE
6. CHECK SHIFT POSITION SIGNAL
(VEHICLE SPEED ABOVE 10 km/h, 6 mph)
Check up±shifting together with terminal TT voltage.
 Gear Position Terminal TT output voltage 1st Gear 0 V 
 2nd Gear
 
 2 V
 3rd Gear 4 V
 3rd Lock±up 5 V
 O/D 6 V
 O/D Lock±up 7 V
HINT: Check for light shocks from up±shifting and for
changes in the tachometer.
If terminal TT Output voltage check cannot be done, do the
check of TT terminal circuit on page AT2±115. AT2±36
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

(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 2
" 1, 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 and 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 59 km/h (37 mph).
(2) Lightly depress the accelerator pedal and check that the
RPM does not change abruptly.
If there is a big jump in RPM, there is no lock±up.
2. D POSITION TEST (MANU PATTERN)
Shift into the D position and hold the accelerator pedal
constant at the full throttle valve opening position, and check
the following points:
(a) Check up±shift operation.
2±3 and 3±O/D up shifts should take place, and shift points
should conform to those shown in the automatic shift sched-
ule.
(See page AT2±116)
HINT:
wO/D up±shift or lock±up will not occur when the engine
coolant temp. is below 605C (1405F) and speed is under
60 km/h (37 mph), or if there is a 10 km/h (6 mph)
difference between the set cruise control speed.
w3rd up±shift or lock±up will not occur when engine
coolant temp. is 355C (955F) and speed is under 40 km/h
(25 mph).
(b) Check for shift shock and slip.
In the same manner, check the shock slip at the 2
" 3 and
3
" O/D up±shifts. AT2±38
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

(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

5. INSPECT AND ADJUST SHIFT LEVER POSITION
When shifting the shift lever from the N position to other posi-
tions, check that the lever can be shifted smoothly and accu-
rately to each position and that the position indicator correctly
indicates the position.
If the indicator is not aligned with the correct position, carry
out the following adjustment procedures:
(a) Loosen the nut on the control shaft lever.
(b) Push the control shaft lever fully rearward.
(c) Return the control shaft lever 2 notches to N position.
(d) Set the shift lever to N position.
(e) While holding the shift lever lightly toward the R position side,
tighten the shift lever nut.
(f) Start the engine and make sure that the vehicle moves
forward when shifting the lever from the N to D position and
reverses when shifting it to the R position.
6. INSPECT AND ADJUST PARK/NEUTRAL POSITION
SWITCH
Check that the engine can be started with the shift lever only
in the N or P position, but not in other positions.
If not as stated above, carry out these adjustment proce-
dures:
(a) Loosen the park/neutral position switch bolt and set the shift
lever to the N position.
(b) Align the groove and neutral basic line.
(c) Hold in position and tighten the bolt.
Torque: 12 NVm (125 kgfVcm, 9 ftVlbf)
For continuity inspection of the park/neutral position switch,
see page AT2±101.
7. INSPECT IDLE SPEED
Idle speed:
650+50 rpm
(In N position and air conditioner OFF)
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±43

DTC.
No.Blinking
PatternCircuitDiagnostic Trouble Code Detection Condition
38
42
46
61
62
63
64
A/T fluid
temp.
sensor
No.1 vehicle
speed sensor
No.4 solenoid
valve
No.2 vehicle
speed sensor
No.1 solenoid
valve
No.2 solenoid
valve
No.3 solenoid
circuit
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
All conditions below are detected for 4 secs. or more:
(2 trip detection logic)*3
(a) No. No.1 vehicle speed sensor signal in 16 pulses of No.2
vehicle speed sensor signal
(b) Vehicle speed: 9 km/h (5.6 mph) or more for or more
(c) Park/neutral position switch: OFF (Other than P or N
position)
All conditions below are detected for 1 sec. or more:
(2 trip detection logic)*3
(a) ECM output duty signal to No.4 solenoid in 90% or higher
duty ratio
(b) Current to No.4 solenoid: 330+100 mA or less
All conditions below are detected:
(2 trip detection logic)*3
(a) No. No.2 vehicle speed sensor signal in 4 pulses of No.1
vehicle speed sensor signal
(b) Vehicle speed: 9 km/h (5.6 mph) or more for 4 secs. or
more
(c) Park/neutral position switch: OFF (Other than P or N
position)
(1) Solenoid resistance of 8 or less is detected (*) times or
more when NO.1 solenoid is energized.
(2) Solenoid resistance of 100 k or more is detected (*) 8 times
or more when No.1 solenoid is not energized.
(*) If the above failure are detected less than 8 times, the ECM
memorizes the malfunction code but the O/D OFF indicator
light does not blink.
(1) Solenoid resistance of 8 or less is detected (*) times or
more when NO.2 solenoid is energized.
(2) Solenoid resistance of 100 k or more is detected (*) 8 times
or more when No.2 solenoid is not energized.
(*) If the above failure are detected less than 8 times, the ECM
memorizes the malfunction code but the O/D OFF indicator
light does not blink.
All conditions below are detected for 1 sec. or more:
(2 trip detection logic)*3
(a) ECM output duty signal to No.3 solenoid in 90% or higher
duty ratio
(b) Current to No.3 solenoid: 450+100 mA or less
DIAGNOSTIC TROUBLE CODE CHART
If a diagnostic trouble code is displayed during the diagnostic trouble code check, check the circuit listed
for that code in the table below and proceed to the page given. AT2±54
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING