TOYOTA SUPRA 1997 Service Repair Manual

N14677
Fuse
(+) (-)
DI-600
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
828 Author
: Date
:
1997 SUPRA (RM502U)
SRS Warning Light System Malfunction (Does not light up, when
ignition switch is in turned to ACC or ON.)
CIRCUIT DESCRIPTION
The SRS warning light is located on the combination meter.
When the SRS is normal, the SRS warning light lights up for approx. 6 seconds after the ignition switch is
turned from LOCK position to ACC or ON position, and then turns off automatically.
If there is a malfunction in the SRS, the SRS warning light lights up to inform the driver of the abnormality.
When terminals Tc and E
1 of the DLC1 are connected, the DTC is displayed by the blinking of the SRS warn-
ing light.
WIRING DIAGRAM
Refer to page DI-598 for the WIRING DIAGRAM.
INSPECTION PROCEDURES
1 Check ECU-B Fuse.
PREPARATION:
Remove the ECU-B fuse.
CHECK:
Check the continuity of ECU-B fuse.
OK:
Continuity
HINT:

Fuse may be burnt out even if it appears to be OK during
visual inspection.

If fuse is OK, install it.
NG Go to step 5.
OK
2 Preparation (See step 1 on page DI-595).
DI4WT-01

W02760AB0119
H00048
ON
Airbag Sensor Assembly
LA
(-)
(+)
H03185
P squib
Spiral
Cable
Airbag Sensor
Assembly D squib
ON
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-601
829 Author
: Date
:
1997 SUPRA (RM502U)
3 Check SRS warning light circuit.
PREPARATION:
(a) Connect negative (-) terminal cable to battery.
(b) Turn the ignition switch to ACC or ON.
CHECK:
Measure the voltage LA terminal of harness side connector of
airbag sensor assembly.
OK:
Voltage: 10 - 14 V
NG Check SRS warning light balb/repair SRS warn-
ing light circuit.
OK
4 Does SRS warning light come on?
PREPARATION:
(a) Disconnect negative (-) terminal cable from the battery.
(b) Connect the airbag sensor assembly connector.
(c) Connect negative (-) terminal cable to battery, and wait
at least 2 seconds.
(d) Turn the ignition switch to ACC or ON.
CHECK:
Check operation of SRS warning light.
NO Check terminal LA of airbag sensor assembly.
If normal, replace airbag sensor assembly.
YES
From the results of the above inspection, the malfunctioning part can now be considered normal.
To make sure of this, use the simulation method to check.

DI-602
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
830 Author
: Date
:
1997 SUPRA (RM502U)
5 Is new ECU-B fuse burnt out again?
NO Using simulation method, reproduce malfunc-
tion symptoms (See page IN-18).
YES
Check harness between ECU- B fuse and
SRS warning light.

H03189
Airbag Sensor
Assembly
Tc
7 21
II1 113
Tc
E1DLC1
BR P-B7
1E 1G
Junction Block No.1 P-B
R (*1)
P-B (*2) 3
11
IF1 R
Tc E1
DTC2 BR 18
IJ1 BR
BR
ED
*1: 2JZ-GE
*2: 2JZ-GTE
R-B
4 3P-B
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-603
831 Author
: Date
:
1997 SUPRA (RM502U)
Tc Terminal Circuit
CIRCUIT DESCRIPTION
By connecting terminals Tc and E1 of the DLC1 the airbag sensor assembly is set in the DTC output mode.
The DTCs are displayed by the blinking of the SRS warning light.
WIRING DIAGRAM
DI4WU-02

H03186
ACC
ON
or LOCK
AB0118
R14305AB0119
H00030
ACC
ON
or
(-)DLC 1
(+)Tc E
1
DI-604
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
832 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURES
HINT:
If the DTC is not displayed, perform the following troubleshooting.
1 Does SRS warning light light up for approx. 6 seconds?
CHECK:
Check operation of SRS warning light after ignition switch is
turned from LOCK position to ACC or ON position.
NO Check SRS warning lights system
(See page DI-557).
YES
2 Check voltage between terminals Tc and E1 of DLC1.
PREPARATION:
Turn the ignition switch to ACC or ON.
CHECK:
Measure the voltage between terminals Tc and E1 of DLC1.
OK:
Voltage: 10 - 14 V
OK Go to step 4.
NG

AB0118
R14304AB0119
H00031
ACC
ON
or
(-)DLC 1
(+)Tc
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-605
833 Author
: Date
:
1997 SUPRA (RM502U)
3 Check voltage between terminal Tc of DLC1 and body ground.
CHECK:
Measure the voltage between terminals Tc of DLC1 and body
ground.
OK:
Voltage: 10 - 14 V
OK Check harness between terminal E
1 of DLC1
and body ground.
NG

AB0117 AB0118 AB0119W02763
H00049
LOCK
Airbag Sensor Assembly
TcACC
ON
or
DI-606
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
834 Author
: Date
:
1997 SUPRA (RM502U)
4 Check airbag sensor assembly.
PREPARATION:
(a) Turn the ignition switch to LOCK.
(b) Disconnect negative (-) terminal cable from the battery,
and wait at least 90 seconds.
(c) Remove the steering wheel pad. (See SR section)
(d) Disconnect the connector of front passenger airbag as-
sembly. (See page RS-21)
(e) Disconnect the connector of airbag sensor assembly.
(See page RS-33)
(f) Insert the service wire into terminal Tc from back side as
shown.
(g) Connect the airbag sensor assembly connector with ser-
vice wire.
(h) Connect negative (-) terminal cable to battery.
(i) Turn the ignition switch to ACC or ON, and wait at least
20 seconds.
(j) Connect the service wire of terminal Tc to body ground.
CHECK:
Check operation of SRS warning light.
OK:
SRS warning light comes on.
NOTICE:
Never make a mistake with the terminal connection posi-
tion as this will cause a malfunction.
OK Check harness between airbag sensor assem-
bly and DLC1.
NG
Replace airbag sensor assembly.

AB0117
W02764H00050
LOCK
Airbag Sensor Assembly
(-)Tc
(+)
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-607
835 Author
: Date
:
1997 SUPRA (RM502U)
If the DTC is displayed without a DTC check procedure, perform the following
troubleshooting.
1 Check resistance between terminal Tc of airbag sensor assembly and body
ground.
PREPARATION:
(a) Turn the ignition switch to LOCK.
(b) Disconnect negative (-) terminal cable from the battery,
and wait at least 90 seconds.
(c) Disconnect the airbag sensor assembly connector.
CHECK:
Check the resistance between terminal Tc of airbag sensor as-
sembly connector and body ground.
OK:
Resistance: 1 MW or higher
NG Repair or replace harness or connector.
OK
Replace airbag sensor assembly.

DI4WV-01
Customer Problem Analysis
Vehicle Brought to Workshop
Problem Symptom ConfirmationSymptom Simulation Probkem does not occur
Matrix Chart of Problem Symptoms
Circuit Inspection
Identification of Problem
Repair
Confirmation Test
EndTitles inside
are titles of pages in this
manual, with the page number indicated in
the bottom portion. See the indicated pages
for detailed explanations. 1
23
4
5
7
Step 5, 7 : Diagnostic steps permitting the use
of the TOYOTA hand-held tester or
TOYOTA break-out-box. P. DI-609
P. DI-615
P. IN-18
P. DI-617
Problem occurs
6
DI-608
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
836 Author
: Date
:
1997 SUPRA (RM502U)
THEFT DETERRENT SYSTEM
HOW TO PROCEED WITH TROUBLESHOOTING
HINT:
Troubleshooting of the theft deterrent system is based on the premise that the door lock control system is
operating normally. Accordingly, before troubleshooting the theft deterrent system, first make certain that
the door lock control system is operating normally.
For troubleshooting using a volt/ohm meter, see page DI-615.
Be sure to use troubleshooting procedure appropriate to the diagnostic tool being used.
Perform troubleshooting in accordance with the procedure on the following page.

DI4WW-01
THEFT DETERRENT SYSTEM Check Sheet
Inspector 's name:
Customer 's Name
Date of VehicleRegistration No.
Registration Year
Frame No.
Odometer Reading / /km
Mile
Weather Conditions
When Problem
Occurred Frequency Problem OccursWeather
Outdoor temperature
/ /

Constant
Sometimes ( Times per day, month)

Once only Brought in

Theft deterrent system cannot be set.

Indicator light does not flash when the theft deterrent system is set.
(It stays on or does not light at all.)

Theft deterrent system
does not operate.
When unlocked using the
door lock knob.

When the engine hood is
opened.

System cannot be
canceled once set.
When door is unlocked using key or wireless door lock control system.

When the key is inserted in the ignition key cylinder and turned to ACC or ON
position.
(However, only when the system has never operated)

When the luggage compartment door is opened with the key.

System cannot be
canceled during warning
operation.
When door is unlocked using key or wireless door lock control system.

When the key is inserted in the ignition key cylinder and turned to ACC or ON
position.

Warning operation starts when the system is set and the door or luggage compartment door is opened with
the key.

Others.
Date Problem First Occurred

Fine
Cloudy
Rainy
Snowy

Various/Others

Hot
Warm
Cool

Cold (Approx. 5F ( 5C))
Problem Symptom
Malfunction

Horns only

Theft deterrent horn only

Headlights only

Taillights only

Starter cut only

Door lock operation only
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
DI-609
837 Author
: Date
:
1997 SUPRA (RM502U)
CUSTOMER PROBLEM ANALYSIS CHECK