1995 TOYOTA SUPRA ignition

Check P squib.
(1) Turn ignition switch to LOCK, and wait at least
2 seconds.
(2) Turn ignition switch to ACC or ON, wait at least
20 seconds.
(3) Clear malfunction code stored in memory. (See
page RS±47)
(4) Turn ignition switch to LOCK, and wait at least
20 seconds.
(5) Turn ignition switch to ACC or ON, and wait at
least 20 seconds.
(6) Using SST, connect terminals Tc and E
1 of DLC1
or DLC2.
SST 09843±18020
(7) Check diagnostic trouble code.
Diagnostic trouble code 53 is not output.
Codes other than code 53 may be output at this
time, but they are not relevant to this check.
(1) Turn ignition switch to LOCK.
(2) Disconnect negative (±) terminal cable from the
battery, and wait at least 90 seconds.
(3) Connect front passenger airbag assembly con±
nector.
(4) Connect negative (±) terminal cable to battery, and
wait at least 2 seconds.
Replace front passenger airbag assembly.
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.
RS±90± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

Check center airbag sensor assembly.
(1) Turn ignition switch to ACC or ON, and wait at
least 2 seconds.
(2) Clear malfunction code stored in memory. (See
page RS±47)
(3) turn ignition switch to LOCK, and wait at
least 20 seconds.
(4) Turn ignition switch to ACC or ON, and wait at
least 20 seconds.
(5) Using SST, connect terminals Tc and E
1 of DLC1
or DLC2.
SST 09843±18020
(6) Check diagnostic trouble code.
Diagnostic trouble code 54 is not output.
Codes other than code 54 may be output at this
time, but they are not relevant to this check.
Replace center airbag sensor assembly.
(1) Connect connector to center airbag sensor
assembly.
(2) Using a service wire, connect D
+ and D± on spiral
cable side of connector between spiral cable and
steering wheel pad.
(3) Using a service wire, connect P
+ and P± on center
airbag sensor assembly side of connector be±
tween center airbag sensor assembly and front
passenger airbag assembly.
(4) Connect negative (±) terminal cable to battery, and
wait at least 2 seconds. RS±94
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

Check P squib.
(1) Turn ignition switch to ACC or ON, and wait at
least 20 seconds.
(2) Clear malfunction code stored in memory. (See
page RS±47)
(3) turn ignition switch to LOCK, and wait at
least 20 seconds.
(4) Turn ignition switch to ACC or ON, and wait at
least 20 seconds.
(5) Using SST, connect terminals Tc and E
1 of DLC1
or DLC2.
SST 09843±18020
(6) Check diagnostic trouble code.
Diagnostic trouble code 54 is not output.
Codes other than code 54 may be output at this
time, but they are not relevant to this check.
Replace front passenger airbag assembly.
(1) Turn ignition switch to LOCK.
(2) Disconnect negative (±) terminal cable from the
battery, and wait at least 90 seconds.
(3) Connect front passenger airbag assembly con±
nector.
(4) Connect negative (±) terminal cable to battery, and
wait at least 2 seconds.
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.
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±95

SRS Warning Light System (Always lit up when ignition switch is in
Lock position.)
CIRCUIT DESCRIPTION
The SRS warning light is located on the cluster finish panel.
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 or DLC2 are connected, the diagnostic trouble code is displayed by the blinking
of the SRS warning light.
RS±96± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

INSPECTION PROCEDURES [P] Preparation [C] Check
Does SRS warning light turn off?
(1) Turn ignition switch to LOCK.
(2) Disconnect negative (±) terminal cable from the
battery, and wait at least 90 seconds.
(3) Disconnect center airbag sensor assembly
connector.
(4) Connect negative (±) terminal cable to battery.
Check operation of SRS warning light.
Replace center airbag sensor assembly.
Check SRS warning light circuit or terminal AB cir-
cuit of DLC1 or DLC2.
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±97

Does SRS warning light light up for approx. 6 seconds?
Check operation of SRS warning light after ignition
switch turned from LOCK position to ACC or ON
position.
Check SRS warning light system.
(See page RS±44)
Check voltage between terminals Tc and E1 of DLC1 and DLC2.
Turn ignition switch to ACC or ON.
Measure voltage between terminals Tc and E
1 of
DLC1 or DLC2.
Voltage: Battery positive voltage
INSPECTION PROCEDURES [P] Preparation [C] Check
HINT: If the diagnostic trouble code is not displayed, do the following troubleshooting:
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±99

Check voltage between terminals Tc of DLC1 or DLC2 and body ground.
Measure voltage between terminals Tc of DLC1 or
DLC2 and body ground.
Voltage: Battery positive voltage
Check harness between terminals E1 of DLC1
or DLC2 and body ground.
Check center airbag sensor assembly.
(1) Turn ignition switch to LOCK.
(2) Disconnect negative (±) terminal cable from the
battery, and wait at least 90 seconds.
(3) Disconnect center airbag sensor assembly con±
nector.
(4) Insert test probe into terminal Tc from back side as
shown.
(5) Connect center airbag sensor assembly con±
nector with check pin.
(6) Connect negative (±) terminal cable to battery.
(7) Turn ignition switch to ACC or ON and wait at
least 20 seconds.
(8) Using service wire, connect test probe of termi±
nal Tc to body ground.
Check operation SRS warning light.
SRS warning light comes on.
NOTICE: Never made a mistake with the terminal
connection position as this will cause a malfunc-
tion.
Check harness between center airbag sensor
assembly and DLC1 or DLC2.
Replace center airbag sensor assembly. RS±100
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

HINT: If the diagnostic trouble code is displayed without a DTC check procedure, perform the following trouble-
shooting.
Repair or replace harness or connector.
Check resistance between terminal Tc of center airbag sensor assembly
and body ground.
(1) Turn ignition switch to LOCK.
(2) Disconnect negative (±) terminal cable from the
battery, and wait at least 90 seconds.
(3) Disconnect center airbag sensor assembly con±
nector.
Check resistance between terminal Tc of center airbag
sensor assembly connector and body ground.
Resistance: 1 M
or Higher
Replace center airbag sensor assembly.
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±101