1995 TOYOTA SUPRA ignition

FRONT PASSENGER AIRBAG
ASSEMBLY REMOVAL AND
INSTALLATION
NOTICE:
wIf the wiring connector of the SRS is disconnected with
the ignition switch at ON or ACC, diagnostic trouble
codes will be recorded.
wNever use airbag parts from another vehicle. When
replacing parts, replace with new parts.
1. DISCONNECT AIRBAG CONNECTOR
(a) Remove negative (±) terminal cable from the battery, and
wait at least 90 seconds.
(b) Remove the glove compartment door finish plate inside the
instrument panel box.
NOTICE: When handling the airbag connector, take care
not to damage the airbag wire harness.
(c) Pull up the connector.
(d) Disconnect the airbag connector.
2. REMOVE THESE PARTS:
(a) Instrument panel box
(See page BO±49)
(b) Heater to register duct No. 4
3. REMOVE FRONT PASSENGER AIRBAG ASSEMBLY
(a) Remove the 4 bolts.
(b) Pull the front passenger airbag assembly to remove it.
CAUTION:
wDo not store the front passenger airbag assembly with
the airbag door facing down.
wNever disassemble the front passenger airbag assembly.
4. INSTALL FRONT PASSENGER AIRBAG ASSEMBLY
(a) Install the front passenger airbag assembly.
(b) Install the 2 bolts to instrument panel reinforcement.
Torque: 21 NVm (210 kgfVcm, 15 ftVlbf)
(c) Install the 2 bolts to instrument panel.
Torque: 8.8 NVm (90 kgfVcm, 78 in.Vlbf)
NOTICE:
wMake sure the front passenger airbag assembly is
installed to the specified torque.
± SUPPLEMENTAL RESTRAINT SYSTEMFRONT PASSENGER AIRBAG ASSEMBLYRS±23

5. DISPOSAL OF FRONT PASSENGER AIRBAG
ASSEMBLY
CAUTION:
wThe front passenger airbag assembly is very hot when
the airbag is deployed, so leave it alone for at least 30
minutes after deployment.
wUse gloves and safety glasses when handling a front
passenger airbag assembly with deployed airbag.
wDo not apply water, etc., to a front passenger airbag
assembly with deployed airbag.
wAlways wash your hands with water after completing the
operation.
When scrapping a vehicle, deploy the airbag and scrap the
vehicle with the front passenger airbag assembly still
installed.
When disposing of front passenger airbag
assembly only
When disposing of the front passenger airbag assembly
only, never use the customer's vehicle to deploy the air-
bag.
Remove the front passenger airbag assembly from the ve-
hicle and be sure to follow the procedure given below when
deploying the airbag.
HINT: Have a battery ready as the power source to deploy the
airbag.
1. REMOVE FRONT PASSENGER AIRBAG ASSEMBLY
(See page RS±23)
CAUTION:
wWhen removing the front passenger airbag assembly,
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.
wStore the front passenger airbag assembly with the
airbag door facing up.
2. FIX FRONT PASSENGER AIRBAG ASSEMBLY TO TIRE
Using a service±purpose wire harness for vehicle, tie down
the front passenger airbag assembly to the tire.
Wire harness: Stripped wire harness section
1.25 mm
2 or more (0.0019 in.2 or more)
HINT: To calculate the square of the stripped wire harness
section
Square = 3.14 X (Diameter)
2 divided by 4
± SUPPLEMENTAL RESTRAINT SYSTEMFRONT PASSENGER AIRBAG ASSEMBLYRS±27

COMPONENTS
FRONT AIRBAG SENSOR REMOVAL
AND INSTALLATION
NOTICE:
wIf the wiring connector of the SRS is disconnected
with the ignition switch at ON or ACC, diagnostic
trouble codes will be recorded.
wNever use SRS parts from another vehicle. When
replacing parts, replace with new parts.
wNever reuse the sensor involved in a collision when
the SRS has deployed.
wNever repair a sensor in order to reuse it.
± SUPPLEMENTAL RESTRAINT SYSTEMFRONT AIRBAG SENSORRS±31

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

Diagnostic trouble code clearance
Using diagnosis check wire:
(a) Connect the 2 service wires to terminals Tc and AB of DLC1
or DLC2.
(b) Turn the ignition switch to ACC or ON and wait approx. 6
seconds.
(c) Starting with the Tc terminal, apply body ground alternately
to terminal Tc and terminal AB twice each in cycles of 1.0
seconds. Confirm that body ground is absolute. Finally, keep
applying body ground to terminal Tc.
HINT: When alternately grounding terminals Tc and AB, re-
lease ground from one terminal and immediately apply it to
the other terminal within an interval of 0.2 second. If diagnos-
tic trouble codes do not clear, repeat the above procedure un-
til the codes are cleared.
(d) Several seconds after doing the clearing procedure, the SRS
warning light will blink in a 50 m sec. cycle to indicate the
codes have been cleared.
Using TOYOTA hand±held tester:
(a) Hook up the TOYOTA hand±held tester to the DLC1 or DLC2.
(b) Clear 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±47

CONNECTORS
Slightly shake the connector vertically and horizontally.
Inspection of connectors
(a) Does the wire harness connecting with its corresponding
part have insufficient slack?
(b) Are the terminals dirty?
(c) Are the terminals making loose contact due to terminals
spread?
WIRE HARNESS
Slightly shake the wire harness vertically and horizontally.
Thoroughly check the connector joint, the fulcrum of the
vibration and the wiring opening in the engine/passenger
compartment panel.
PARTS AND SENSORS
Gently tap the part or sensor considered to be the problem
caused and check if the malfunction will occur.
CAUTION: Do not apply vibration to the center airbag
sensor assembly.
VIBRATION METHOD: When vibration seems to be the major cause.
SYMPTOM SIMULATION
ªIntermittent troubles or problemsº are the malfunctions about which the customer has a complaint, but which
do not occur and cannot be confirmed in the workshop. The intermittent problems also include complaints about
the SRS warning light going on and off erratically.
The self±diagnostic system stores the circuit of the intermittent problem in memory even if the ignition switch
is turned off.
For accurate diagnosis of the problems, ask the customer to obtain as much information as possible following
the customer problem analysis check sheet (See page RS±43) and try to reproduce the intermittent problem.
The problem simulation methods described below are the effective ways to reproduce the problem conditions
by applying vibration, heat, and humidity. RS±48
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

DIAGNOSTIC TROUBLE CODE MATRIX CHART
If a malfunction code is displayed during the diagnostic trouble code check, check the circuit listed for that code
in the table below (Proceed to the page given for that circuit.).
 
 DTC No. 
 Diagnosis 
 Page
 (Normal)*1 
Source voltage drop RS±52
 
 
 
11
 
 
 

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


Front airbag sensor or center airbag sensor assembly malfunction
 
 
 
RS±54
 
 
 
12 
 
 

Short in squib circuit (to B+)


Open in front airbag sensor circuits
 
 
 
RS±60
 13 
Short in D squib circuit (between D+ wire harness and D± wire harness) RS±66
 
 14
 
 
Open in D squib circuit
 
 RS±73
 
 15
 
 
Open in front airbag sensor circuit
 
 RS±78
 
 22*2 
 
SRS warning light system malfunction 
 RS±82
 31 
Center airbag sensor assembly malfunction RS±86
 
 53
 
 
Short in P squib circuit
 
 RS±87
 
 54
 
 
Open in P squib circuit
 
 RS±92
HINT:
*1 When the SRS warning light remains lit up and the diagnostic trouble code is the normal code, this means
a source voltage drop.
*
2 Code 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 confirmed.
PROBLEM SYMPTOM CHART
Proceed with troubleshooting of each circuit in the table below.
RS±96
RS±98
Problem SymptomInspection ItemPage

Tc terminal circuit

SRS warning light system
Always lit up, when ignition
switch is in LOCK position.

With the ignition switch at ACC or ON, the SRS warning light
sometimes lights up after approx. 6 seconds have elapsed.

SRS warning light is always lit up even when ignition switch
is in the LOCK position.

Diagnostic trouble code not displayed.

SRS warning light is always lit up with the DTC check procedure.

Diagnostic trouble code displayed without Tc and E1 terminal
correction.
RS±50± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

INSPECTION PROCEDURES [P] Preparation [C] Check
(1) Turn ignition switch to LOCK.
(2) Disconnect center airbag sensor assembly con±
nector.
(3) Turn ignition switch ON. But do not start engine.
(4) Measure voltage at IG
2 or ACC on connector
wire harness side of center airbag sensor as±
sembly and operate electric system (defogger,
wiper, headlight, heater blower, etc.).
Voltage: 6 V Ð 11.5 V at IG
2 and ACC.
(5) Turn electric system switch OFF.
(6) Turn ignition switch to LOCK.
(7) Remove voltmeter and connect center sensor
assembly connector.
Preparation.
Does SRS warning light turn off?
Turn ignition switch ON.
Operate electric system checked in [1] (4) and
check that SRA warning light goes off.
Turn ignition switch ON.
Check battery and charging system.
(See charging system section)
Check diagnostic trouble code, and if a malfunc-
tion code is output, perform troubleshooting ac-
cording to malfunction code. If a normal code is
output, replace center airbag sensor assembly.
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±53