1995 TOYOTA SUPRA warning light

There are some maintenance and inspection
items which are considered to be the owner's re-
sponsibility. They can be performed by the owner
or be can have them done at a service shop.
These items include those which should be
checked on a daily basis, those which, in most
cases, do not require (special) tools and those
which are considered to be reasonable for the
owner to perform. Items and procedures for gen-
eral maintenance are as follows:
OUTSIDE VEHICLE
1. TIRES
(a) Check the pressure with a gauge. Adjust if
necessary.
(b) Check for cuts, damage, uneven or excessive
wear.
2. WHEEL NUTS
When checking the tires, check the nuts for
looseness or for missing nuts. If necessary,
tighten them.
3. WINDSHIELD WIPER BLADES
Check for wear or cracks whenever they do not
wipe clean. Replace if necessary.
4. FLUID LEAKS
(a) Check underneath for leaking fuel, oil, water or
other fluid.
(b) If you smell gasoline fumes or notice any leak,
have the cause found and corrected.
5. DOORS AND ENGINE HOOD
(a) Check that all doors including the trunk lid
operate smoothly, and that all latches lock
securely.
(b) Check that the engine hood secondary latch
secures the hood from opening when the
primary latch is released.
INSIDE VEHICLE
6. LIGHTS
(a) C h e c k t h a t t h e headlights, stop lights,
tail±lights, turn signal lights, and other lights
are all working.
(b) Check the headlight aiming.7. WARNING LIGHT AND BUZZERS
Check that all warning lights and buzzers
function properly.
8. HORN
Check that it is working.
9. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
10. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
11. WINDSHIELD DEFROSTER
Check that the air comes out from the defrost-
er outlet when operating the heater air condi-
tioner at defroster mode.
12. REAR VIEW MIRROR
Check that it is mounted securely.
13. SUN VISORS
Check that they move freely and are
mounted securely.
14. STEERING WHEEL
Check that it has the specified freeplay. Be
alert for changes in steering condition, such
as excessive steering effort, excessive free-
play or strange noise.
15. SEATS
(a) Check that all front seat controls such as seat
adjusters, seatback recliner, etc. operate
smoothly.
(b) Check that all latches lock securely in any
position.
(c) Check that the locks hold securely in any
latched position.
(d) Check that the head restraints move up and
down smoothly and that the locks hold
securely in any latched position.
(e) For folding±down rear seat backs, check that
the latches lock securely.
16. SEAT BELTS
(a) Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly.
(b) Check that the belt webbing is not cut, frayed,
worn or damaged.
17. ACCELERATOR PEDAL
Check the pedal for smooth operation and
uneven pedal effort or catching.
GENERAL MAINTENANCE
± MAINTENANCEGENERAL MAINTENANCEMA±17

GENERAL DESCRIPTION
The SUPRA is equipped with an SRS (Supplemental Restraint System), which comprises a driver
airbag, and front passenger airbag if fitted. Failure to carry out service operations in the correct
sequence could cause the SRS to unexpectedly deploy during servicing, possibly leading to a seri-
ous accident. Further, if a mistake is made in servicing the SRS, it is possible the SRS may fail to
operate when required. Before performing servicing (including removal or installation of parts, in-
spection or replacement), be sure to read the following items carefully, then follow the correct pro-
cedure described in the repair manual.
1. Malfunction symptoms of the SRS are difficult to confirm, so the diagnostic trouble codes become the most
important source of information when troubleshooting. When troubleshooting the SRS, always inspect the
diagnostic trouble codes before disconnecting the battery.
(See page RS±44)
2. Work must be started after 90 seconds from the time the ignition switch is turned to the ºLOCKº
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 from the battery, the SRS may deploy.)
When the negative (±) terminal cable is disconnected from the battery, memory of the clock and audio sys-
tems will be canceled. So before starting work, make a record of the contents memorized by the audio
memory system. When work is finished, reset the audio systems as before and adjust the clock. To avoid
erasing the memory of each memory system, never use a back±up power supply from outside the vehicle.
3. Even in cases of a minor collision where the SRS does not deploy, the steering wheel pad, front passenger
airbag assembly, front airbag sensors and center airbag sensor assembly should be inspected.
(See pages RS±10, 20, 30, and 33)
4. Never use SRS parts from another vehicle. When replacing parts, replace them with new parts.
5. Before repairs, remove the airbag sensors if shocks are likely to be applied to the sensors during repairs.
6. Never disassemble and repair the steering wheel pad, front passenger airbag assembly, front airbag
sensors or center airbag sensor assembly in order to reuse it.
7. If the steering wheel pad, front passenger airbag assembly, front airbag sensors or center airbag sensor
assembly have been dropped, or if there are cracks, dents or other defects in the case, bracket or
connector, replace them with new ones.
8. Do not expose the steering wheel pad, front passenger airbag assembly, front airbag sensors or center
airbag sensor assembly directly to hot air or flames.
9. Use a volt/ohmmeter with high impedance (10 k
/V minimum) for troubleshooting the system's electrical
circuits.
10. Information labels are attached to the periphery of the SRS components. Follow the instructions on the
notices.
11. After work on the SRS is completed, check the SRS warning light.
(See page RS±44)
12. If the vehicle is equipped with a mobile communication system, refer to the precaution in the IN section. RS±2
± SUPPLEMENTAL RESTRAINT SYSTEMGENERAL DESCRIPTION

OPERATION
FUNCTION OF COMPONENTS
1. STEERING WHEEL PAD (with AIRBAG)
The inflater and bag of the SRS are stored in the steering
wheel pad and cannot be disassembled. The inflater con-
tains a squib, igniter charge, gas generant, etc., and inflates
the bag when instructed by the center airbag sensor assem-
bly.
2. SPIRAL CABLE (in COMBINATION SWITCH)
A spiral cable is used as an electrical joint from the vehicle
body side to the steering wheel.
3. FRONT PASSENGER AIRBAG ASSEMBLY
The inflater and bag of the SRS are stored in the front pas-
senger airbag assembly and cannot be disassembled.
The inflater contains a squib, igniter charge, gas generant,
etc., and inflates the bag when instructed by the center airbag
sensor assembly.
4. SRS WARNING LIGHT
The SRS warning light is located on the cluster finish panel.
It goes on to alert the driver of trouble in the system when a
malfunction is detected in the center airbag sensor assembly.
In normal operating conditions when the ignition switch is
turned to the ACC or ON position, the light goes on for about
6 seconds and then goes off.
5. FRONT AIRBAG SENSOR
A front airbag sensor is mounted inside each of the front fend-
ers. The sensor unit is a mechanical type. When the sensor
detects a deceleration force above a predetermined limit,
contacts is made in the sensor, sending a signal to the center
airbag sensor assembly. The sensor cannot be disas-
sembled. RS±4
± SUPPLEMENTAL RESTRAINT SYSTEMOPERATION

RS±43
RS±44
RS±44
RS±47
RS±44
RS±50
RS±48
RS±52 TO 101
RS±47
RS±44
Vehicle Brought to Workshop
Customer Problem Analysis
Warning Light Check
Diagnostic Trouble Code Check and Recording
Malfunction Code Clearance
Diagnostic Trouble Code Check and Recording
Diagnostic Trouble Code Matrix Chart
Symptom Simulation
Malfunction Code
Malfunction Code
Circuit Inspection
Identification of Problem
Repair
Malfunction Code Clearance
Malfunction Code
Normal Code
Normal Code
Normal
Code
Does Not Light Up
Remains ON
Malfunction Code
Normal Code
Conformation Test
Diagnostic Trouble Code Check
Diagnostic steps permitting the use of
The TOYOTA hand±held tester.
HOW TO PROCEED WITH TROUBLESHOOTING
RS±42± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

CUSTOMER PROBLEM ANALYSIS CHECK SHEET
 Supplemental Restraint System Check Sheet
Inspector 's
Name:
   Registration No. 
 Customer 's Name  Registration Year //
   Frame No. 
 
 
Date Vehicle
Brought In 
 //
 
 Odometer Reading
 
 
km
Miles
 
 
Date Problem First Occurred 
 //
 Weather 
Fine
Cloudy
Rainy
Snowy
Other_ _ _ _ _ _ _
 Temperature Approx.°C (°F) p A rox.C (F)
 
 
 
Vehicle Operation
 
 
 

Starting
Idling

Driving [
Constant speed
Acceleration
Deceleration

Other_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ]
 
 
 
Road Conditions
 
 
 
 
 
 
 
 
 
Details of Problem
 
 
 
 
 
 
 
 
 
 
 
 
 
Vehicle Inspection, Repair History
Prior to Occurrence of Malfunction
(Including Supplemental Restraint
System)
 
 
 
 
 
 
 
Diagnosis System Inspection
 
 SRS Warning Light
 
 1st Time
 
 
Remains ON
Sometimes Lights Up
Does Not Light Up
 Inspection 2nd Time 
Remains ON
Sometimes Lights Up
Does Not Light Up
 Diagnostic Trouble 1st Time 
Normal Code
Malfunction Code [Code ]
 Code Inspection 2nd Time 
Normal Code
Malfunction Code [Code. ]
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±43

DIAGNOSIS INSPECTION
SRS warning light check
(a) Turn the ignition switch to ACC or ON and check that the SRS
warning light lights up.
(b) Check that the SRS warning light goes out after approx. 6
seconds.
HINT:
wWhen the ignition switch is at ACC or ON and the SRS
warning light remains on or flashes, the center airbag
sensor assembly has detected a malfunction code.
wIf, after approx. 6 seconds have elapsed, the SRS
warning light sometimes lights up or the SRS warning
light light up even when the ignition switch is OFF, a
short in the SRS warning light circuit can be considered
likely. Proceed to ºSRS warning light systemº on page
RS±97.
Diagnostic trouble code check
Using diagnosis check wire:
1. OUTPUT DIAGNOSTIC TROUBLE CODE
(a) Turn the ignition switch to ACC or ON position and wait
approx. 20 seconds.
(b) Using SST, connect terminals Tc and E
1 of the DLC1 or
DLC2.
SST 09843±18020
NOTICE: Never make a mistake with the terminal connec-
tion position as this will cause a malfunction. RS±44
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

2. READ DIAGNOSTIC TROUBLE CODE
Read the 2±digit diagnostic trouble code as indicated by the
number of times the SRS warning light blinks. As an example,
the blinking patterns, normal, 11 and 31 are as shown on the
illustration.
wNormal code indication
The light will blink 2 times per second.
wMalfunction code indication
The number represented by the first blinking code out-
put indicates the first digit of a 2±digit diagnostic trouble
output.
After a 1.5 second pause, the second blinking code will
indicate the second digit.
If there are 2 or more codes, there will be a 2.5 second
pause between each code. After all the codes have
been output, there will be a 4.0 second pause and they
will all be repeated.
HINT:
wIn the event of a number of trouble codes, indication will
start from the smallest numbered code.
wIf it does not output a diagnostic trouble code or outputs
a diagnostic trouble code without terminal connection,
proceed to the Tc terminal circuit inspection on page
RS±99.
Using TOYOTA hand±held tester:
(a) Hook up the TOYOTA hand±held tester to the DLC1 or DLC2.
(b) Read the diagnostic trouble codes by following the prompts
on the tester screen.
HINT: Please refer to the TOYOTA hand±held tester opera-
tor 's manual for further details.
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±45

System normal

Source voltage drop

Short in squib circuit or front
airbag sensor circuit (to ground)

Front airbag sensor
center airbag sensor
assembly malfunction

Short in squib circuit (to B+)

Open in front airbag sensor
circuits

Short in driver airbag squib circuit
(between D+ wire harness and D±
wire harness)

Open in driver airbag squib circuit

Open in front airbag sensor circuit

SRS warning light system mal±
function

Center airbag sensor assembly
malfunction

Short in front passenger airbag
squib circuit

Open in front passenger airbag
squib circuit

Battery

Center airbag sensor assembly

Squib (driver airbag and front pas±
senger airbag)

Front airbag sensor

Spiral cable

Center airbag sensor assembly

Wire harness

Squib (driver airbag and front pas±
senger airbag)

Front airbag sensor

Spiral cable

Center airbag sensor assembly

Wire harness

Steering wheel pad (squib)

Spiral cable

Center airbag sensor assembly

Wire harness

Steering wheel pad (squib)

Spiral cable

Center airbag sensor assembly

Wire harness

Front airbag sensor

Center airbag sensor assembly

Wire harness

SRS warning light

Center airbag sensor assembly

Wire harness

Center airbag sensor assembly

Front passenger airbag assembly
(squib)

Center airbag sensor assembly

Wire harness

Front passenger airbag assembly
(squib)

Center airbag sensor assembly

Wire harness
HINT:
*
1
wWhen the SRS warning light remains lit up and the diagnostic trouble code is the normal code, this means
a source voltage drop.
This malfunction is not stored in memory by the center airbag sensor assembly and if the power source
voltage returns to normal, after approx. 10 seconds the SRS warning light will automatically go out.
*
2
wCode 22 is recorded when a malfunction occurs in the SRS warning light system.
If an open malfunction occurs in the SRS warning light system, the SRS warning light does not light up,
so that until the malfunction is repaired, the diagnostic trouble codes (including code 22) cannot be con-
firmed.
wWhen 2 or more codes are indicated, the lowest numbered code will appear first.
wIf a code not listed on the chart is displayed, the center airbag sensor assembly is faulty. RS±46
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING