TOYOTA SUPRA 1997 Service Repair Manual

H03233
P squib
Spiral
CableAirbag Sensor
Assembly
D squib
ACCON
DLC1Code 53
E
1Tcor
DI-590
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
818 Author
: Date
:
1997 SUPRA (RM502U)
3 Check airbag sensor assembly.
PREPARATION:
(a) Connect the connector to airbag sensor assembly.
(b) Connect negative (-) terminal cable to battery, and wait
at least 2 seconds.
CHECK:
(a) Turn the ignition switch to ACC or ON and wait at least 20
seconds.
(b) Clear malfunction code stored in memory.
(See page DI-557)
(c) Turn the ignition switch to LOCK, and wait at least 20 se-
conds.
(d) Turn the ignition switch to ACC or ON, and wait at least
20 seconds.
(e) Using SST, connect the terminals Tc and E
1 of DLC1.
SST 09843-18020
(f) Check DTC.
OK:
DTC 53 is not output.
HINT:
Codes other than code 53 may be output at this time, but they
are not relevant to this check.
NG Replace airbag sensor assembly.
OK

H03234
P squib
Spiral
CableAirbag Sensor
Assembly
D squib
ACC
ON
DLC1Code 53 or
E
1Tc
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-591
819 Author
: Date
:
1997 SUPRA (RM502U)
4 Check P squib.
PREPARATION:
(a) Turn the ignition switch to LOCK.
(b) Disconnect negative (-) terminal cable from the battery,
and wait at least 90 seconds.
(c) Connect the front passenger airbag assembly connector.
(d) Connect negative (-) terminal cable to battery, and wait
at least 2 seconds.
CHECK:
(a) Turn the ignition switch to LOCK, and wait at least 20 se-
conds.
(b) Turn the ignition switch to ACC or ON and wait at least 20
seconds.
(c) Clear malfunction code stored in memory.
(See page DI-557)
(d) Turn the ignition switch to LOCK, and wait at least 20 se-
conds.
(e) Turn the ignition switch to ACC or ON, and wait at least
20 seconds.
(f) Using SST, connect the terminals Tc and E
1 of DLC1.
SST 09843-18020
(g) Check DTC.
OK:
DTC 53 is not output.
HINT:
Codes other than code 53 may be output at this time, but they
are not relevant to this check.
NG Replace front passenger airbag assembly.
OK
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.

R14287R05898H07923
P squibAirbag Sensor
Assembly
D squib
Spiral
Cable
P-
(+) (-)P
+
DI-592
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
820 Author
: Date
:
1997 SUPRA (RM502U)
1
DTC 54 Open in P Squib Circuit
CIRCUIT DESCRIPTION
The P squib circuit consists of the airbag sensor assembly and front passenger airbag assembly.
It causes the airbag to deploy when the airbag deployment conditions are satisfied.
For details of the function of each component, see FUNCTION OF COMPONENTS on page RS-2.
DTC 54 is recorded when an open is detected in the P squib circuit.
DTC No.DTC Detecting ConditionTrouble Area
54

Open circuit in P+
wire harness or P- wire harness of squib.

P squib malfunction.

Airbag sensor assembly malfunction.
Front passenger airbag assembly (P squib)

Airbag sensor assembly

Wire harness
WIRING DIAGRAM
Refer to page DI-588 for the WIRING DIAGRAM.
INSPECTION PROCEDURES
1 Preparation (See step 1 on page DI-595).
2 Check P squib circuit.
CHECK:
For the connector (on the airbag sensor assembly side) be-
tween the airbag sensor assembly and front passenger airbag
assembly measure the resistance between P
+ and P-.
OK:
Resistance: Below 1W
NG Repair or replace harness or connector be-
tween airbag sensor assembly and front pas-
senger airbag assembly.
OK
DI4WQ-01

AB0069R05895AB0118AB0119R05170N19819
H07974
P squibAirbag Sensor
Assembly
D squib
Spiral
Cable
ACC
ON
or
Code 54
DLC1
E
1Tc
P+P-
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-593
821 Author
: Date
:
1997 SUPRA (RM502U)
3 Check airbag sensor assembly.
PREPARATION:
(a) Connect the connector to airbag sensor assembly.
(b) Using a service wire, connect P
+ and P- on airbag sensor
assembly side of connector between airbag sensor as-
sembly and front passenger airbag assembly.
(c) Connect negative (-) terminal cable to battery, and wait
at least 2 seconds.
CHECK:
(a) Turn the ignition switch to ACC or ON and wait at least 20
seconds.
(b) Clear malfunction code stored in memory.
(See page DI-557)
(c) Turn the ignition switch to LOCK, and wait at least 20 se-
conds.
(d) Turn the ignition switch to ACC or ON, and wait at least
20 seconds.
(e) Using SST, connect the terminals Tc and E
1 of DLC1.
SST 09843-18020
(f) Check DTC.
OK:
DTC 54 is not output.
HINT:
Codes other than code 54 may be output at this time, but they
are not relevant to this check.
NG Replace airbag sensor assembly.
OK

H03236
P squibAirbag Sensor
Assembly
D squib
Spiral
Cable
ACC
ON
or
DLC1Code 54
E
1Tc
DI-594
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
822 Author
: Date
:
1997 SUPRA (RM502U)
4 Check P squib.
PREPARATION:
(a) Turn the ignition switch to LOCK.
(b) Disconnect negative (-) terminal cable from the battery,
and wait at least 90 seconds.
(c) Connect the front passenger airbag assembly connector.
(d) Connect negative (-) terminal cable to battery, and wait
at least 2 seconds.
CHECK:
(a) Turn the ignition switch to ACC or ON, and wait at least
20 seconds.
(b) Clear malfunction code stored in memory.
(See page DI-557)
(c) Turn the ignition switch to LOCK, and wait at least 20 se-
conds.
(d) Turn the ignition switch to ACC or ON, and wait at least
20 seconds.
(e) Using SST, connect the terminals Tc and E
1 of DLC1.
SST 09843-18020
(f) Check DTC.
OK:
DTC 54 is not output.
HINT:
Codes other than code 54 may be output at this time, but they
are not relevant to this check.
NG Replace front passenger airbag assembly.
OK
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.

W00786
Relay Block No.2 Junction Block No.1Airbag Sensor
Assembly
2
21B 1J1J
1J1G 1G6
10 3 8
3
G 4
4
W ALT
AM2
Battery IB1 4
Ignition SwitchJunction Block No.1ACC 16
15
AM16 B-W
72
W-RG-R
B-O
IG2 W
22
2A
Relay Block No.2
W
B
1W-RCIG
IGN
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-595
823 Author
: Date
:
1997 SUPRA (RM502U)
DTC Normal Source Voltage Drop
CIRCUIT DESCRIPTION
The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the airbag sensor assembly in
case the source voltage drops.
When the battery voltage drops, the voltage-increase circuit (DC-DC converter)functions to increase the
voltage of the SRS to normal voltage.
The diagnosis system malfunction display for this circuit is different to other circuits-when the SRS warning
light remains lit up and the DTC is a normal code, source voltage drop is indicated.
Malfunction in this circuit is not recorded in the airbag sensor assembly, and the source voltage returns to
normal, the SRS warning light automatically goes off.
DTC No.DTC Detecting ConditionTrouble Area
NormalSource voltage drop.
Battery

Airbag sensor assembly
WIRING DIAGRAM
DI4WR-01

R05894 AB0117
H00001
P squibAirbag Sensor
Assembly
D squib
Spiral
Cable LOCK
AB0119
W02766H00041
Airbag Sensor Assembly
ON
ACC
IG2
(-)(+)
DI-596
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
824 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURES
1 Preparation.
PREPARATION:
(a) Disconnect negative (-) terminal cable from the battery,
and wait at least 90 seconds.
(b) Remove the steering wheel pad (See SR Section).
(c) Disconnect the connector of front passenger airbag as-
sembly (See page RS-21).
(d) DIsconnect the connector of airbag sensor assembly
(See page RS-33).
CAUTION:
Store the steering wheel pad with the front surface facing
upward.
2 Check source voltage.
PREPARATION:
(a) Connect negative (-) terminal cable to the battery.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage at IG2 or ACC on sensor and operate elec-
tric system. (defogger, wiper, headlight, heater blower, etc)
OK:
Voltage: 10 - 14 V
NG Check the harness between battery and airbag
sensor assembly, and check the battery and
charging system.
OK

AB0119AB0234H07975
ON
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-597
825 Author
: Date
:
1997 SUPRA (RM502U)
3 Does SRS warning light turn off ?
PREPARATION:
(a) Turn the ignition switch to LOCK.
(b) Connect the steering wheel pad connector.
(c) Connect the front passenger airbag assembly connector.
(d) Connect the airbag sensor assembly connector.
(e) Turn the ignition switch ON.
CHECK:
Operate electric system checked in (defogger, wiper, headlight,
heater blower, etc.) and check that SRS warning light goes off.
NO Check for DTCs. If a DTC is output, trouble-
shooting for the DTC. If a normal code is output,
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.

W03534
21E 1G
1E1G II1
IF1
IF1
II1
1E 1B3
7
9
4
2
131211 21
2
Battery
1B
5 11 DLC1
Relay Block No.2
ALT
Power
Power
Airbag Sensor
Assembly
Junction Block No.1
Junction Block No.1
SRS Waring Light215
Junction Block No.1
*1: 2JZ-GE Engine
*2: 2JZ-GTE Engine ECU-BTc
ABB (*1)
(*2) B-Y
LA 12
W-RP-B R (*1)
(*2)
P-B
P-B
2
2A2P-B
7
Tc
W-L
ABTc DLC2
R
4
12B-Y
B B
B
B DI-598
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
826 Author
: Date
:
1997 SUPRA (RM502U)
SRS Warning Light System Malfunction (Always lit up, when igni-
tion switch is in LOCK position.)
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
DI4WS-01

AB0117R05902
H07976
LOCK
P squib
Spiral
CableAirbag Sensor
Assembly
D squib
AB0117
W02765H00044
LOCK
Airbag Sensor Assembly
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI-599
827 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURES
1 Preparation.
PREPARATION:
(a) Disconnect negative (-) terminal cable from the battery,
and wait at least 90 seconds.
(b) Remove the steering wheel pad (See SR Section).
(c) Disconnect the connector of front passenger airbag as-
sembly (See page RS-21).
CAUTION:
Store the steering wheel pad with the front surface facing
upward.
2 Does SRS warning light turn off?
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.
(d) Connect negative (-) terminal cable to battery.
CHECK:
Check operation of SRS warning light.
NG Check SRS warning light circuit or terminal AB
circuit of DLC1.
OK
Replace airbag sensor assembly.