1995 TOYOTA SUPRA warning light

TERMINALS OF ECU
 No. Symbol Terminal Name No. Symbol Terminal Name
 T8±1 +B2 Power Source T9±1 +B1 Power Source
 T8±2 ACT± Door Lock Motor T9±2 ± ± 
 T8±3
 
 ACT+
 
 Door Lock Motor
 
 T9±3
 
 ±
 
 ±
 T8±4 E Ground 
T9 4
 
DSWL
 Luggage Compartment Door Courtesy
 T8±5 ± ± T9±4 DSWL 
Luggage Com artment Door Courtesy
Switch
 T8±6 RLY Power Main Relay T9±5 L1 Door Lock Control Switch (Lock) 
 T8±7
 
 IG
 
 Ignition Switch ºONº
 
 T9±6
 
 UL3
 
 Door Key Lock and Unlock Switch
 T8±8 ACC Ignition Switch ºACCº T9±7 DSWD Door Open Detection Switch
 T8±9 ± ± T9±8 UL1 Door Lock Control Switch (Unlock)
 
T9 9
 
LUG
 Luggage Compartment Door Key Lock T9±9 LUG Luggage Com artment Door Key Lock
and Unlock Switch
 T9±10 HEAD Headlight Control Relay 
 T9±11
 
 SH
 
 Theft Deterrent Horn
 T9±12 IND Security Indicator Light
 T9±13 ± ±
 T9±14 FOD Engine Hood Courtesy Switch  
LSWD
 
Door Unlock Detection Switch or Door T9±15 LSWD,
UL2 Door Unlock Detection Switch or Door
K L k d U l k S it h
T9±15
UL2Key Lock and Unlock Switch 
 T9±16
 
 ±
 
 ±
 T9±17 ± ±
 T9±18 ± ±
 T9±19 DSWP Door Open Detection Switch 
 T9±20
 
 KSW
 
 Key Unlock Warning Switch
 T9±21 LSWP Door Unlock Detection Switch
 T9±22 L2 Door Key Lock and Unlock Switch
 T9±23 TAIL Taillight Control Relay 
 T9±24
 
 HORN
 
 HORN Relay
 T9±25 SRLY Ignition Switch ºSTº
± BODY ELECTRICAL SYSTEMBE±125THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

 Terminals Symbols Condition Standard Value
 
 
T9±12±Ground
(IND±Ground) 
 W±L±Ground
 
 Always
 
 Below 270

 T9±14±T8±4 
VR WB
 Engine hood courtesy switch ON (hood opened). Below 1
 
 
T9 14 T8 4
(FOD±E) 
 
VR±WB 
 Engine hood courtesy switch OFF (hood closed). 
 1 M
or higher
 T9±15±T8±4 LW W B Door unlock detection switch ON (door opened). Below 1

 
T9 15 T8 4
(LSWD±E) LW±WB Door unlock detection switch OFF (door closed). 1 M
or higher
 
T9 15 T8 4
  Door key lock and unlock switch ºunlockº position Below 1
 
 
T9±15±T8±4
(UL2±E) 
 W±WB 
 Door key lock and unlock switch OFF or ºlockº
position 
 1 M
or higher
   
Door open detection switch (passenger's) ON
 
Below 1
 
 T9±19±T8±4
 
 RL WB
 
 
Door oen detection switch ( assenger s) ON
(door opened). 
 
Below 1

 
T9 19 T8 4
(DSWP±E) 
RL±WB
 Door open detection switch (passenger's) OFF 1M
or higher
   
Door oen detection switch ( assenger s) OFF
(door closed). 
1 M
or higher
 T9±20±T8±4 
YWB
 Key unlock warning switch ON. Below 1

 
T9 20 T8 4
(KSW±E) Y±WB Key unlock warning switch OFF. 1 M
or higher
 
T9±21±T8±4
 
GB WB
 Door unlock detection switch ON (door opened). Below 1
 
 
T9 21 T8 4
(LSWP±E) 
 
GB±WB 
 Door unlock detection switch OFF (door closed).
 
 1 M
or higher
 
T9 22 T8 4
  Door key lock and unlock switch ºlockº position. Below 1

 
 
T9±22±T8±4
(L2±E) 
 
GY±WB 
 
Door key lock and unlock switch OFF or ºunlockº
position. 
 1 M
or higher
 
 T9±23±T8±4
(TAIL±E) 
 GW±WB
 
 Light control switch ºTAILº position.
 
 10±14 V
 
 T9±24±T8±4
(HORN±E) 
 LR±WB
 
 Horn switch OFF.
 
 10±14 V
 
 T9±25±Ground
(SRLY±Ground) 
 L±O±Ground
 
 Ignition switch is turned to ºSTº position.
(When park / neutral position switch ºPº position) 
 10±14 V
± BODY ELECTRICAL SYSTEMBE±127THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

Door Courtesy Switch Circuit
CIRCUIT DESCRIPTION
The door courtesy switch goes on when the door is opened and goes off when the door is closed.
INSPECTION PROCEDURE
(See page BE±123).
Check and repair open door warning light circuit
Check and replace theft deterrent ECU. *1.
Check operation of open door warning light.
Check that open door warning light comes on when each door is opened, and goes off when all
doors are closed.
*1: When there is a malfunction that the theft
deterrent system cannot be set, proceed to
the next numbered circuit inspection shown
on matrix chart (See page BE±123).
Check for open in harness and connector between theft deterrent and door
lock ECU and door courtesy switch (See page
IN±30).
Repair or replace harness or connector.
± BODY ELECTRICAL SYSTEMBE±147THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

(See page BE±42).
BE±169.
Proceed to next circuit inspection shown on matrix
chart (See page
BE±170).
(1) See input signal check on page BE±169.
(2) Check the indicator light when the parking brake
lever is pulled up.
Check operation of brake warning light.
Check voltage between terminal PKB of cruise control ECU connector and
body ground.
(1) Turn ignition switch ON.
(2) Measure voltage between terminal PKB of cruise
control ECU connector and body ground, when
the parking brake lever is pulled up and released.
Remove cruise control ECU with connectors still con-
nected.
Input signal check.
The indicator light goes off when the parking brake lever
is pulled up.
Check that the brake warning light in the instrument panel comes on when the parking brake lever is
pulled up with the engine running, and the light goes off when the parking brake lever is released.
Check brake warning light circuit
Parking brake lever
Proceed to next circuit inspection shown on matrix
chart (See page
BE±170).
Voltage
Pulled up
Released
Check for open in harness and connector between cruise control ECU and
brake warning light.
Repair or replace harness or connector.
Check and replace cruise control ECU. BE±190
± BODY ELECTRICAL SYSTEMCRUISE CONTROL SYSTEM

  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

DIAGNOSIS SYSTEM
INDICATOR CHECK
When the ignition switch is turned ON, check that the ABS
warning light goes on for 3 seconds.
HINT: If the indicator check result is not normal, proceed to
troubleshooting for the ABS warning light circuit (See page
BR±107)
DIAGNOSTIC TROUBLE CODE CHECK
1. Turn the ignition switch ON.
2. Disconnect the Short Pin from DLC1.
3. Using SST, connect terminals Tc and E1 of DLC2 or DLC1.
SST 09843±18020
4. Read the diagnostic trouble code from the ABS warning light
on the combination meter.
HINT: If no code appears, inspect the diagnostic circuit or
ABS warning light circuit (See page BR±112 or BR±107).
As an example, the blinking patterns for normal code and
codes 11 and 21 are shown on the left.
5. Codes are explained in the code table on page BR±56.
6. After completing the check, disconnect terminals Tc and E1,
and turn off the display.
If 2 or more malfunctions are indicated at the same time, the
lowest numbered diagnostic trouble code will be displayed
first. BR±54
± BRAKE SYSTEMANTI±LOCK BRAKE SYSTEM (ABS)

ECU DATA MONITOR USING TOYOTA
HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester to the DLC2.
2. Monitor the ECU data by following the prompts on the scan
tool screen.
HINT: TOYOTA hand±held tester has a ºSnapshotº function
which records the monitored data.
Please refer to the TOYOTA hand±held tester operator's
manual for further details.
DIAGNOSTIC TROUBLE CODE
CLEARANCE
1. Using SST, connect terminals Tc and E1 of DLC2 or DLC1.
SST 09843±18020
2. IG switch ON.
3. Clear the diagnostic trouble codes stored in ECU by
depressing the brake pedal 8 or more times within 3 seconds.
4. Check that the warning light shows the normal code.
5. Remove the SST from the terminals of DLC2 or DLC1.
6. Connect the Short Pin to DLC1.
HINT: Cancellation can also be done by removing the ECU±B
fuse, but in this case, other memory systems will also be can-
celled out.
ECU TERMINAL VALUES
MEASUREMENT USING TOYOTA
BREAK±OUT±BOX AND TOYOTA
HAND±HELD TESTER
1. Hook up the TOYOTA hand±held tester and TOYOTA
break±out±box to the vehicle.
2. Read the ECU input/output values by following the prompts
on the tester screen.
HINT: TOYOTA hand±held tester has a ºSnapshotº function.
This records the measured values and is effective in the diag-
nosis of intermittent problems.
Please refer to the TOYOTA hand±held tester/TOYOTA
break±out±box operators manual for further details.
± BRAKE SYSTEMANTI±LOCK BRAKE SYSTEM (ABS)BR±55