sensor TOYOTA SUPRA 1995 Service Owners Manual

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

 
 Trouble Area
 
 O/D OFF Indicator
Light *1Blinks
 
 Memory *2
 
 See
Page
Trouble Area
Light *1 Blinks
Memory
Page 
 
 
 
 

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

A/T fluid temp. sensor

ECM
 
 
 
 
 

 
 
 
 
 

 
 
 
 
 
AT2±70
 
 
 
 
 
 
 

Harness or connector between No.1 vehicle speed sensor and
ECM

No.1 vehicle speed sensor

Telltale light RH

ECM
 
 
 
 
 
 
 

 
 
 
 
 
 
 

 
 
 
 
 
 
 
AT2±72
 
 
 

Harness or connector between No.4 solenoid valve and ECM

No.4 solenoid valve
 
 
 
 
 
 
 
 
 AT2±75
 
 

ECM 
 

 
 

 
 
AT 2±75
 
 
 
 
 
 

Harness or connector between No.2 vehicle speed sensor and
ECM

No.2 vehicle speed sensor

ECM 
 
 
 
 
 

 
 
 
 
 
 

 
 
 
 
 
 
AT2±79
 
 
 
 
 

Harness or connector between No.1 solenoid valve and ECM

No.1 solenoid valve

ECM 
 
 
 
 

 
 
 
 
 

 
 
 
 
 
AT2±82
 
 

Harness or connector between No.2 solenoid valve and ECM

No.2 solenoid valve 
 
 
 
 
 AT2±82 
 


ECM 
 

 
 

 
 

AT 2±82
 
 
 

Harness or connector between No.3 solenoid valve and ECM

No.3 solenoid valve
 
 
 X
 
 
 
 
 
 AT 2 8 5 

No.3 solenoid valve

ECM X  AT2±85
    
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±55

DTC.
No.Blinking
PatternCircuitDiagnostic Trouble Code Detection Condition
67
77
89
O/D direct
clutch speed
sensor
No.5 solenoid
circuit
TRAC ECU
circuit
All conditions below are detected for 4 secs. or more:
(2 trip detection logic)*3
(a) Gear change not being performed.
(b) Gear position: 1st, 2nd or 3rd
(c) T/M input shaft rpm: Less than 300 rpm
(d) T/M output shaft rpm: 1000 rpm or more
Any of condition below are detected:
(2 trip detection logic)*3
(a) SLT
± terminal: 0 V or 5 V for 1 sec. or more.
All conditions below are detected for 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.
AT2±56± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

 Trouble Area O/D OFF Indicator
Light *1Blinks
 Memory *2 See
Page Trouble Area Light *1 Blinks Memory  Page
 
 
 
 
 

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

O/D direct clutch speed sensor

ECM
 
 
 
 
 

 
 
 
 
 

 
 
 
 
 
AT2±89
 
 
 
 
 
 

Harness or connector between No.5 solenoid valve and

ECM

No.5 solenoid valve

ECM
 
 
 
 
 
 

 
 
 
 
 
 

 
 
 
 
 
 
AT2±92
 
 
 
 
 
 

Harness or connector between TRAC ECU and ECM.

TRAC ECU
 
 
 
 
 
 

 
 
 
 
 
 

 
 
 
 
 
 
AT2±95
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±57

*1: ºOº mark means ºO/D OFFº light blinks once every 2 seconds.
ºXº mark means ºO/D OFFº light never blinks.
*2: ºOº marks means the ECM memorizes the malfunction code if the ECM detects the diagnostic trouble code
detection condition.
*3: This indicates items for which º2 trip detection logicº is used. With this logic, when a logic malfunction is
first detected, the malfunction is temporarily stored in the ECM memory. If the same case is detected again
during the second drive test, this second detection causes the O/D OFF indicator light to blink. The 2 trip
repeats the same mode twice. (However, the IG switch must be turned OFF between the 1st trip and 2nd
trip.)
HINT:
wIf the malfunction returns to normal while a malfunction warning is being output, the O/D OFF indicator
light stops blinking and goes off.
However, the diagnostic trouble code is retained in memory until it is cleared from memory.
wIf the diagnosis system outputs a diagnostic trouble code even though the O/D OFF indicator was not
blinking, there is intermittent trouble. Check all the connections in the circuits corresponding to that
code.
wCodes 42, 62, 63 and 64 are limited to short or open circuits in the electrical system comprised of the
solenoids, wire harnesses, and connectors. The ECM is unable to detect mechanical trouble (sticking,
for example) in the solenoid valves.
wIf the speed sensors No.1 and No.2 happen to fail simultaneously, the ECM will neither alert the driver
by blinking the O/D OFF indicator nor record any diagnostic trouble code. It will, however, decide that
the vehicle can be driven only in 1st and none of the other gears, shifting upward will then be
prohibited. AT2±58
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

Chapter 1. Electronic Circuit
AT2±72AT2±75AT2±79AT2±82AT2±85AT2±89AT2±97
Suspect Area
Symptom
Vehicle does not move in any forward position and reverse
position
No up±shift
No down±shift
No lock±up
Vehicle does not move in particular position or positions
Harsh engagement
No engine braking
1st " 2nd
2nd " 3rd
3rd " O/D
O/D " 3rd
3rd " 2nd
2nd " 1st
N " D
Large shift shock or Engine stalls when starting off or stopping.
*No pattern select
No.1 Vehicle speed
sensor circuit
See Page
No lock±up off
Slip or Shudder
Poor acceleration
No kick±down
Lock±up
Any driving position
Forward and reverse
Any particular position
Shift point too high or too low
Up±shifts to 2nd while in L position
Up±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
No.1, No.2 solenoidcircuitNo.2 Vehicle speed
sensor circuitNo.4 solenoid
circuitNo.3 solenoid
circuit(Sub)±throttle
position sensor circuitO/D direct clutch
speed sensor circuit
* The automatic transmission in not shifted into the manual mode when the automatic transmission fluid
temperature is too high. AT2±64
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

AT2±101AT2±99AT2±103AT2±105AT2±108AT2±111EG±312AT2±60AT2±66AT2±68AT2±92BR±128AT2±70
Park/neutral position
switchPattern select switch
circuitStop light switch
circuitKick±down switch
circuitO/D switch O/D OFF
indicator light circuitEngine coolant temp.
sensor circuitO/D cancel signal
circuitECMNo.5 solenoid
circuitOFF±Vehicle repair
matrix chartOn±Vehicle repair
matrix chartTRAC ECUA/T fluid temp.
sensor circuit
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±65

WIRING DIAGRAM 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 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
AT2±70± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING

INSPECTION PROCEDURE
Check A/T fluid temp. sensor.
Check harness and connector between A/T fluid temp. sensor and ECM
(See page IN±30).
Replace A/T fluid temp. sensor.
Repair or replace harness or connector.
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

11 0°C (230°F): Approx. 0.78 k

20°C (68°F) and 110°C (230°F).
Check and replace ECM.
± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTINGAT2±71

CIRCUIT DESCRIPTION
Transmission
Output Shaft
No.1 Vehicle
Speed Sensor
The No. 1 vehicle speed sensor outputs a 4±pulse signal for every revolution of the rotor shaft, which
is rotated by the transmission output shaft via the driven gear. After this signal is converted into a more
precise rectangular waveform by the waveform shaping circuit inside the combination meter, it is then
transmitted to the engine control module. The ECM determines the vehicle speed based on the fre-
quency of these pulse signals.
Diagnostic Trouble Code Detection ConditionDTC No.Trouble Area
42

No. 1 vehicle Speed sensor

Telltale light RH

Harness or connector between No. 1 vehicle
speed sensor and ECM

ECMAll conditions below are detected for 4 secs. or
more. (2 trips detection logic)*
(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
(c) Park/neutral position switch:
OFF (Other than P or N position)
HINT: In test mode, diagnostic trouble code 42 is output when vehicle speed is 5 km/h (3 mph) or
below.


Waveform between terminals SP1 and E2 when vehicle speed is approx. 20 km/h (12 mph).
HINT: As the vehicle's speed increases, the signal output from
SP1 increases.
* See page AT2±58
Driven Gear
No.1 Vehicle Speed Sensor
Telltale Light
RH
DTC 42 No.1 Vehicle Speed Sensor Signal Circuit
AT2±72± A340E (2JZÐGTE) AUTOMATIC TRANSMISSIONTROUBLESHOOTING