sensor TOYOTA SUPRA 1995 Service Repair Manual

Check operation of No.1 vehicle speed sensor (see page BE±46).
Repair or replace harness or connector between
telltale light RH and No.1 vehicle speed sensor.
Replace No.1 vehicle speed sensor.
AT2±74± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

The No.4 solenoid valve controls the hydraulic pressure acting on
the brakes and clutches of the planetary gear units when gears are
shifted and performs smooth gear shifting.
The ECM determines optimum operating pressure according to
the signals from the throttle position sensor, vehicle speed sensor
and O/D clutch speed sensor and controls the volume of current
flow to the solenoid valve.
The amount of electric current to the solenoid is controlled by the
(*) duty ratio of ECM output signals, causing momentary change
to the hydraulic pressure acting on the clutches during gear shift-
ing. When the duty ratio is high, the hydraulic pressure acting on
the clutches is now.
(*) Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle.
For example, if A is the period of continuity in one cycle, and B is the period of non±continuity, then
Diagnostic Trouble Code Detection ConditionDTC No.Trouble Area
46

No. 4 solenoid valve

Harness or connector between No.4
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.4 solenoid in
90% or higher duty ratio.
(b) Current to No.4 solenoid:
330 + 100 mA or less
(O/D OFF indicator light doesn't blink)

* See page AT2±58

Waveform between terminals SLN
and E1 when engine is idling.
Waveform between terminals SLN
and E1 during shift change.
Lock±up
operation
pressure
Current flow to
solenoid
Duty Ratio =
CIRCUIT DESCRIPTION

100 (%)
DTC 46 No.4 Solenoid Valve Circuit (For Accumulator Back
Pressure Modulation)
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±75

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

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

DTC No.Trouble Area
67

O/D direct clutch speed sensor

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

ECMAll conditions below are detected for 4 secs. or
more.
(2 trips detection logic)*
(a) Gear position: 1st, 2nd or 3rd
(b) T/M input shaft rpm: 1000 rpm or more
(c) T/M output shaft rpm: Less than 300 rpm
(d) NSW OFF (other than P or N position)
Diagnostic Trouble Code Detection Condition

*: See page AT2±58

Waveform between terminals NCO+ and NCO± during engine idling.
This sensor detects the rotation speed of the O/D input shaft
from the rotation of the O/D direct clutch drum.
Its construction is the same as that of the No.2 vehicle speed
sensor (See page AT2±79).
By comparing the O/D direct clutch speed signal and the No.2
vehicle speed sensor signal, the ECM detects the shift timing
of the gears and appropriately controls the engine torque and
hydraulic pressure in response to various conditions, thus
performing smooth gear shift.O/D Direct Clutch Drum
O/D Direct Clutch
Speed Sensor
CIRCUIT DESCRIPTION
DTC 67 O D Direct Clutch Speed Sensor Circuit
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±89

Check O/D direct clutch speed sensor.
Remove the O/D direct clutch speed sensor from
the transmission (See page AT2±17).
Measure resistance between the terminals 1 and 2
of the O/D direct clutch speed sensor.
Resistance: 560 Ð 680 
Check and repair harness and connector between
ECM and O/D direct clutch speed sensor (See page
IN±30).

Check the speed sensor function
Check voltage between the 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.
Replace O/D direct clutch speed sensor.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±91

DTC 89 TRAC ECU Circuit
CIRCUIT DESCRIPTION
When the transmission is in the shift up or stall condition, the TRAC ECU sends a sub±throttle valve close
signal to the sub±throttle actuator.
 DTC No. Diagnostic Code Detection Condition Trouble Area 
 
 
 
 
 
 
 
 
89
 
 
 
 
 
 
 
 
 

All conditions below are detected 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.
 
 
 
 
 
 
 
 
 

Harness or connector between TRAC ECU
and ECM

TRAC ECU
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±95

Throttle Position Sensor Circuit
CIRCUIT DESCRIPTION
The throttle position sensor detects the throttle valve opening angle and sends signals to ECM.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±97

INSPECTION PROCEDURE
Check main throttle position signal.
Voltage changes from 0 V to 8 V by stages.
Turn ignition switch ON.
Do not depress the brake pedal during the test. The
voltage will stay at 0 V if depressed.
Check voltage at the terminal TT of the DLC2 while
gradually depressing the accelerator pedal from
the fully closed position to the fully opened position.
(Close) Throttle Valve Opening Angle (Open)
Proceed to next circuit inspection shown on
matrix chart (See page AT2±64).
Replace throttle position sensor.
Repair or replace harness or connector.
Check main (sub)±throttle position sensor. (see page EG±292, 293)
Check harness and connector between ECM and Main (Sub)±throttle
position sensor (See page IN±30).
Check and replace ECM.
AT2±98± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

Pattern Select Switch Circuit
CIRCUIT DESCRIPTION
The ECM memory contains the shift programs for the NORMAL and MANUAL patterns, 2 position, 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.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±105