1995 TOYOTA SUPRA sensor

INSPECTION PROCEDURE
Proceed to next circuit inspection shown on matrix
chart (See page
BE±170).
(1) Turn ignition switch ON.
(2) Measure voltage between terminal IDL of ECU
connector and body ground, when the throttle
valve is fully closed and fully opened.
Check voltage between terminal IDL of ECU connector and body ground.
Check throttle position sensor.
Measure resistance between terminals 1 and 2 of
throttle position sensor connector, when the throttle
valve is fully closed and fully opened.
(1) Remove cruise control ECU with connectors still
connected.
(2) Disconnect ECM and ABS & TRAC ECU
connector.
Disconnect throttle position sensor connector.
Throttle valve position
Fully opened
Fully closed
Voltage
Throttle valve position
Fully opened
Fully closed
Voltage
Repair or replace harness or connector.
Check and replace ECU.
Check for open and short in harness and connector between ECU and throttle
position sensor, throttle position sensor and body ground (See page
IN±30).
± BODY ELECTRICAL SYSTEMCRUISE CONTROL SYSTEMBE±185

ECU Power Source Circuit
CIRCUIT DESCRIPTION
The ECU power source supplies power to the actuator and sensors, etc. Terminal GND and the cruise control
ECU case are grounded.
WIRING DIAGRAM
INSPECTION PROCEDURE
Check ECU±IG fuse.
Remove ECU±IG fuse from J/B No.1.
Check continuity of ECU±IG fuse.
Continuity
Check for short in all the harness and components
connected to the ECU±IG fuse (See attached wiring
diagram).
± BODY ELECTRICAL SYSTEMCRUISE CONTROL SYSTEMBE±193

  TACHOMETER (ON±VEHICLE) 
 Standard indication (rpm) Allowable range (rpm)
 700 630 ± 770
 1000 915 ± 1115
 2000 1920 ± 2220
 3000 2890 ± 3350
 4000 3940 ± 4400
50005025 ± 5425 
6500
 
6650 ± 6950 
7000
 
7025 ± 7625  OD/TRIP METER (CONNECTOR CONNECTED) 
  1 ± Ground (Ignition SW position ON) Battery positive voltage  4 ± Ground (Light Control SW position TAIL or HEAD) Battery positive voltage  5 ± 7 (Ignition SW ON and drive the vehicle slowly) OV eBattery positive voltage  6 ± 7 (Ignition SW ON and drive the vehicle slowly) OV emore than 5V  8 ± Ground (Constant) Battery positive voltage 
 
 
10 ± Ground (Ignition SW ON, Light Control SW TAIL or
HEAD and turn the Light Control Rheostat
knob to clockwise) 
 
 6V " 0V
  FUEL RECEIVER GAUGE 
 A ± B Approx. 269.7

 A ± C Approx. 123.5

 B ± C Approx. 146.2

  FUEL SENDER GAUGE 
  Float position: F Approx. 4.0

  Float position: 1/2 Approx. 55.0

  Float position: E Approx. 107.0

  ENGINE COOLANT TEMPERATURE RECEIVER GAUGE 
 A ± B Approx. 229.7

 A ± C Approx. 54.0

 B ± C Approx. 175.7

  ENGINE COOLANT TEMPERATURE SENDER GAUGE 
  50 °C (122.0 °F) 160 ± 240

  120 °C (248.0 °F) 17.1 ± 21.2

  LIGHT FAILURE SENSOR 
  3 ± Ground (Light Control SW position OFF) No voltage
  3 ± Ground (Light Control SW position TAIL or HEAD) Battery positive voltage
  4 ± Ground (Ignition SW position LOCK or ACC) No voltage
  4 ± Ground (Ignition SW position ON) Battery positive voltage
  7 ± Ground (Stop Light SW position OFF) No voltage
  7 ± Ground (Stop Light SW position ON) Battery positive voltage
 8 ± Ground (Engine stop)No voltage 
8 ± Ground (Engine running)
 
Battery positive voltage 
INTEGRATION RELAY (Seat Belt Warning)
 
  1 ± Ground (Constant) Battery positive voltage  9 ± Ground (Ignition SW LOCK or ACC) No voltage  9 ± Ground (Ignition SW ON) Battery positive voltage
BE±202± BODY ELECTRICAL SYSTEMSERVICE SPECIFICATIONS

SRS (Supplemental Restraint System)
The 1995 SUPRA is equipped with an SRS, such as the driver airbag and front passenger airbag assembly.
Failure to carry out service operations in the correct sequence could cause the SRS to deploy, possibly
leading to a serious accident.
When removing or installing of airbag parts and the yellow wire harness and connector for the airbag is
necessary, refer to the precautionary notices in the RS section before performing the operation.
wWork must be started after 90 seconds from the time the ignition switch is set to the LOCK position
and the negative (±) terminal cable is disconnected from the battery.
(The SRS is equipped with a back±up power source so that if work is started within 90 seconds of
disconnecting the negative (±) terminal cable of the battery, the SRS may deploy.)
wTo avoid erasing the memory of each memory system, never use a back±up power supply from
outside the vehicle.
wBefore repairs, remove the airbag sensors if shocks are likely to be applied to the sensors during
repairs.
wThe front airbag sensor set bolt has been anti±rust treated. When the sensor is removed, always
replace the set bolt with a new one.
wIf the front airbag sensors, center airbag sensor assembly, steering wheel pad or front passenger
airbag assembly have been dropped, or if there are cracks, dents or other defects in the case, bracket
or connector, replace them with new ones.
wNever use SRS parts from another vehicle. When replacing parts, replace them with new parts.
wDo not expose the front airbag sensors, center airbag sensor assembly, steering wheel pad or front
passenger airbag assembly directly to hot air or flames.
wThe SRS wire harness is integrated with the cowl wire harness assembly. The wires for the SRS wire
harness are encased in a yellow corrugated tube. All the connectors for the system are also a standard
yellow color. If the SRS wire harness becomes disconnected or the connector becomes broken due
to an accident, etc., repair or replace it. (See RS section)
wThe steering wheel must be fitted correctly to the steering column with the spiral cable at the neutral
position; otherwise, cable disconnection and other troubles may result. Refer to RS section of this
manual concerning correct steering wheel installation.
wWhen removing or handling the steering wheel pad or front passenger airbag assembly, it should be
placed with their top surface facing up. In this case, the twin±lock type connector lock lever should
be in the locked state and care should be taken to place it so the connector will not be damaged.
(Storing the pad with its metallic surface up, the front passenger airbag assembly with the airbag door
facing down may lead to a serious accident if the airbag inflates for some reason.)
wGrease should not be applied to the steering wheel pad or the front passenger airbag assembly, and
they should not be cleaned with detergents of any kind.
wStore the steering wheel pad or the front passenger airbag assembly where the ambient temperature
remains below 93°C (200°F), without high humidity and away from electrical noise.
wInformation labels are attached to the periphery of the SRS components. Follow the notices.
wWhen the ignition switch is at ACC or ON and the SRS warning light remains on, the center airbag
sensor assembly has detected a malfunction code. (See RS section)
± BODYGENERAL INFORMATIONBO±5

INSTRUMENT PANEL DISASSEMBLY
1. REMOVE THESE PARTS FROM INSTRUMENT PANEL
(a) Defroster nozzle garnish
(b) Defroster nozzle
(c) Solar sensor
(d) Speakers
(e) Side defroster No.1 nozzle
(f) No.1 bracket
(g) Heater to register No.5 duct
(h) No.4 register
(i) Heater to register No.1 duct
(j) No.3 register
(k) Striker plate
(l) Instrument panel box light switch
(m) Room temperature sensor
(n) Theft deterrent and door lock ECU
(o) Power steering computer
(p) Audio mounting No.1 and No.2 bracket
(q) No.2 and No.3 bracket
(r) No.1 pins
2. REMOVE INSTRUMENT PANEL WIRE HARNESS
INSTRUMENT PANEL ASSEMBLY
Assembly is in the reverse order of disassembly.
INSTRUMENT PANEL INSTALLATION
Installation is in the reverse order of removal.
± BODYINSTRUMENT PANELBO±51

FRONT SPEED SENSOR
COMPONENTS
FRONT SPEED SENSOR REMOVAL
Installation is in the reverse order of removal.
AFTER INSTALLATION, CHECK SPEED SENSOR SIG-
NAL (See page BR±62)
1. DISCONNECT CONNECTOR
(a) Remove the front fender splash shield.
(b) Disconnect the speed sensor connector.
2. REMOVE SPEED SENSOR
(a) Remove the 3 clamp bolts holding the sensor harness to the
body and upper suspension arm.
Torque: 5.4 NVm (55 kgfVcm, 48 in.Vlbf)
(b) Remove the speed sensor from the steering knuckle.
Torque: 7.8 NVm (80 kgfVcm, 69 in.Vlbf)
(c) Remove the O±ring from the speed sensor. BR±48
± BRAKE SYSTEMANTI±LOCK BRAKE SYSTEM (ABS)

REAR SPEED SENSOR
COMPONENTS
REAR SPEED SENSOR REMOVAL
Installation is in the reverse order of removal.
AFTER INSTALLATION, CHECK SPEED SENSOR SIG-
NAL (See page BR±62)
1. DISCONNECT SPEED SENSOR CONNECTOR
(a) Remove the rear seat cushion and seat back.
(b) Remove the quarter trim panel.
(c) Disconnect the speed sensor connector, and pull out the
sensor wire harness with the grommet.
2. REMOVE SPEED SENSOR
(a) Remove the 2 clamp bolts holding the sensor wire harness
to the body and upper arm.
Torque: 5.4 NVm (55 kgfVcm, 48 in.Vlbf)
(b) Remove the speed sensor from the axle carrier.
Torque: 7.8 NVm (80 kgfVcm, 69 in.Vlbf)
± BRAKE SYSTEMANTI±LOCK BRAKE SYSTEM (ABS)BR±49

P. BR±84
P. BR±86 ~ BR±89
P. BR±24
P. BR±86
P. BR±88P. BR±92
P. BR±104 ~ BR±165P. BR±166
Vehicle brought to workshop
Perform troubleshooting in accordance with the procedure on the following pages.
Items insideare titles of pages in this manual,
with the page number in the bottom portion. See the pages
for detailed explanations.
Customer Problem Analysis
Check and Clear Diagnostic Trouble Codes (Precheck)
Symptom
does not occur
Problem Symptom ConfirmationSymptom Simulation
Symptom
occurs
Diagnostic Trouble Code CheckNormal code
Malfunction code
Diagnostic Trouble Code ChartProblem Symptoms Chart
Circuit InspectionSensor CheckCheck for Fluid Leakage
Identification of Problem
Repair
Confirmation Test
EndStepDiagnostic steps permitting the use of the TOYOTA
hand±held tester or TOYOTA break±out box.
HOW TO PROCEED WITH TROUBLESHOOTING
BR±52± BRAKE SYSTEMANTI±LOCK BRAKE SYSTEM (ABS)