TOYOTA SUPRA 1995 Service Repair Manual
Manufacturer: TOYOTA, Model Year: 1995, Model line: SUPRA, Model: TOYOTA SUPRA 1995Pages: 2543, PDF Size: 53.25 MB
Page 561 of 2543

Check No.4 solenoid valve.
Replace No.4 solenoid valve.
1. Jack up the vehicle.
2. Remove oil pan.
3. Disconnect the connector
Measure resistance between terminal 1 and 2 of
solenoid connector.
Resistance: 5.1 Ð 5.5
Check solenoid resistance
Check solenoid operation
Connect positive lead with an 8 Ð 10 W bulb to
terminal 1 of solenoid connector and negative
lead to terminal 2, then check the movement of the
valve.
When battery positive
voltage is applied.Valve moves in
direction in illustration
at left.
When battery positive
voltage is cut off.
direction in illustration
at left.
Valve moves in
Check solenoid's operation
1. Prepare a variable power supply.
2. Connect positive lead of the variable power
supply to terminal 1 of solenoid connector and
negative lead to terminal 2.
3. Check the movement of the valve when the
voltage is gradually increased. (A current
greater than 1A should not be supplied.)
As the voltage is increased, the valve should move
slowly in the direction.
4. Check the movement of the valve when the volt
age is cut off.
The valve should return in the direction.
INSPECTION PROCEDURE
Go to step [2].
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±77
Page 562 of 2543

Check harness and connector between battery and No.4 solenoid valve,
No.4 solenoid valve and ECM (See page IN±30).
Repair or replace harness or connector.
Proceed to next circuit inspection shown on matrix
chart (See page AT2±64). However, when diagnos-
tic trouble code 46 is displayed, check and replace
ECM.
AT2±78± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING
Page 563 of 2543

CIRCUIT DESCRIPTION
The No. 2 vehicle speed sensor detects the rotation speed of the transmission output shaft and sends
signals to the ECM. The ECM determines the vehicle speed based on these signals. An AC voltage
is generated in the No.2 vehicle speed sensor coil as the rotor mounted on the output shaft rotates,
and this voltage is sent to the ECM.
The gear shift point and lock±up timing are controlled by the ECM based on the signals from this vehicle
speed sensor and the throttle position sensor signal.
If the No.2 vehicle speed sensor malfunctions, the ECM uses input signals from the No.1 vehicle speed
sensor as a back±up signal.
No.2 Vehicle Speed Sensor
No.2 Vehicle Speed Sensor
Generated
Waveform
DTC No.Trouble Area
61
No. 2 vehicle speed sensor
Harness or connector between No.2
vehicle speed sensor and ECM
ECM
All conditions below are detected. (2 trips
detection logic)*
(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)
Diagnostic Trouble Detection Condition
*: See page AT2±58
Waveform between terminals SP2+ and SP2± when vehicle speed is approx. 60 km/h (37 mph).
5 V/division
2 msec./division
DTC 61 No.2 Vehicle Speed Sensor Circuit
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±79
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WIRING DIAGRAM
INSPECTION PROCEDURE
Check resistance between terminals SP2+ and SP2± of ECM connector.
Proceed to next circuit inspection shown on matrix
chart (See page AT2±64).
Connect the Check Harness A to the ECM. (See
page EG±510).
Check resistance between terminals SP2
+ and
SP2± of ECM.
Resistance: 560 Ð 680
Go to step [2].
AT2±80± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING
Page 565 of 2543

Check No.2 vehicle speed sensor.
Replace No.2 vehicle speed sensor.
Remove No.2 vehicle speed sensor from trans-
mission (See page AT2±16).
Measure resistance between terminals 1 and 2 of
No.2 vehicle speed sensor.
Resistance: 560 Ð 680
Check and repair harness and connector between
ECM and No.2 vehicle speed sensor (See page
IN±30).
Check the speed sensor's function
Check voltage between terminals 1 and 2 of the
speed sensor when a magnet is put close to the
front end of the speed sensor then taken away
quickly.
Voltage is generated intermittently.
The voltage generated is extremely low.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±81
Page 566 of 2543

DTC 62 63 No.1 No.2 Solenoid Valve Circuit
CIRCUIT DESCRIPTION
Shifting from 1st to O/D is done in combination with ON and OFF of the No.1 and No.2 solenoid valves
controlled by ECM. If an open or short circuit occurs in either of the solenoid valves, the ECM controls the
remaining normal solenoid to allow the vehicle to be operated smoothly (Fail safe function).
Fail Safe Function
If either of the solenoid valve circuits develops a short or an open, the ECM turns the other solenoid ON
and OFF to shift the gear positions shown in the table below. If both solenoids malfunction, the hydraulic
control is not made electronically and can only be operated manually.
Manual shifting, as shown in the following table must be done (In the case of a short circuit, the ECM stops
sending current to the short circuited solenoid).
Pi
NORMAL
NO 1 SOLENOID
MALFUNCTIONING
NO 2 SOLENOID
MALFUNCTIONING
BOTH SOLENOIDS
MALFUNCTIONING
Posi-
tion
Solenoid
valve
Gear
Solenoid
valve
Gear
Solenoid valve
Gear
Gear when shift selector
is manually operated No.1 No.2 Gear No.1 No.2 Gear No.1 No.2 Gear is manually operated
ON OFF 1st X ON 3rd ON X 1st O/D
D
ON
ON
2nd
X
ON
3rd
OFF
X
O/D
O/D
D
OFF ON 3rd X ON 3rd OFF X O/D O/D
OFF OFF O/D X OFF O/D OFF X O/D O/D
ON OFF 1st X ON 3rd ON X 1st 3rd
2 (S) ON ON 2nd X ON 3rd OFF X 3rd 3rd
()
OFF ON 3rd X ON 3rd OFF X 3rd 3rd
L
ON OFF 1st X OFF 1st ON X 1st 1st L ON ON 2nd X ON 2nd ON X 1st 1st
X: Malfunctions
Check the No.1 solenoid when diagnostic trouble code 62 is output and check the No.2 solenoid when
diagnostic trouble code 63 is output.
DTC No.
Diagnostic Trouble Code Detection Condition
Trouble Area
62, 63
(a) Solenoid resistance is 8 or lower (short circuit) when
solenoid is energized.
(b) Solenoid resistance is 100 k or higher (open circuit)
when solenoid is not energized.
The ECM checks for an open or short circuit in the No.1
and No.2 solenoid circuit when it changes gear position.
The ECM records DTC 62 or 63 if condition (a) or (b) is
detected once, but it does not blink the O/D OFF indicator
light.
After the ECM detects the condition (a) or (b) continuously
8 times or more, it causes the O/D OFF indicator light to
blink until condition (a) or (b) disappears.
After that, if the ECM detects condition (a) or (b) one, it
starts blinking the O/D OFF indicator light again.
Solenoid valve
Harness or connector between sole±
noid and ECM
ECM
AT2±82± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING
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WIRING DIAGRAM
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±83
Page 568 of 2543

INSPECTION PROCEDURE
Check No.1 No.2 solenoid valves.
1. Jack up the vehicle.
2. Remove the oil pan.
3. Disconnect the solenoid connector.
Measure resistance between the solenoid con-
nector and solenoid body.
Resistance: 10 Ð 16
Replace solenoid valve.
Electrical Check
Connect positive lead to terminal of solenoid con-
nector, negative lead to solenoid body.
The solenoid makes an operating noise.
1. Remove the oil pan.
2. Remove the No.1 and No.2 solenoid valves.
1. Applying 490 kPa (5 kgf/cm
2, 71 psi) of
compressed air, check that the solenoid valves
do not leak air.
2. When battery positive voltage is supplied
to the solenoid valves, check that the sole±
noid valves open.
Mechanical Check
Repair or replace harness or connector.
Proceed to next circuit inspection shown on matrix
chart (See page AT2±64). However, when diagnostic
trouble code 62 or 63 is displayed, check and replace
ECM.
Check harness and connector between ECM and solenoid (See page IN±30).Check harness and connector between ECM and solenoid (See page IN±30).
AT2±84± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING
Page 569 of 2543

The No.3 solenoid valve is provided for lock±up operations. The
lock±up operation pressure is controlled by the linear solenoid for
smooth engagement.
The amount of current flow to the solenoid is controlled by the duty
ratio (See page AT2±75) of ECM output signal. The higher the duty
ratio becomes, the higher the lock±up hydraulic pressure becomes
during the lock±up operation. If the malfunction occurs in this cir-
cuit and diagnostic trouble code 64 is stored in memory, but the
O/D OFF indicator light does not blink.
Diagnostic Code Detection ConditionDTC No.Trouble Area
64
No.3 solenoid valve
Harness or connector between No.3
solenoid valve and ECM
ECMAll conditions below are detected for 1 sec. or
more. (2 trips detection logic)*
(a) ECM outputs duty signal to No.3 solenoid in
90% or higher duty ratio.
(b) Current to No.3 solenoid:
450 + 100 mA or less.
*: See page AT2±58
Waveform between terminals SLN±
and E1 when engine is idling.
Waveform between terminals SLN±
and E1 during shift change.
CIRCUIT DESCRIPTION
DTC 64 No. 3 Solenoid Valve Circuit (For Lock±up Control Pressure
Modulation)
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±85
Page 570 of 2543

WIRING DIAGRAM
AT2±86± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING