1995 TOYOTA SUPRA warning light

Check SRS warning light circuit.
Repair SRS warning light circuit.
Does SRS warning light come on?
Using simulation method, reproduce mal-
function symptoms (See page RS±48).
Check terminal LA of center airbag sensor assem-
bly and electrical connection check mechanism. If
normal, replace center airbag sensor assembly.
(1) Disconnect center airbag sensor assembly
connector.
(2) Connect negative (±) terminal cable to battery.
(3) Turn ignition switch to ACC or ON.
Measure voltage LA terminal of harness side connec-
tor of center airbag sensor assembly.
Voltage: Battery positive voltage
(1) Disconnect negative (±) terminal cable from the
battery.
(2) Connect center airbag sensor assembly connec±
tor.
(3) Connect negative (±) terminal cable to battery,
and wait at least 2 seconds.
(4) Turn ignition switch to ACC or ON
Check operation of SRS warning light.
SRS warning light comes on.
Check harness between ECU±B fuse and SRS
warning light.
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.
Is new ECU±B fuse burnt out again?
RS±84± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

HINT: If diagnostic trouble code 22 is output, do the following troubleshooting:
Is diagnostic trouble code 22 output again?
Repair SRS warning light circuit.
(1) Turn ignition switch to LOCK, and wait at least
2 seconds.
(2) Turn ignition switch to ACC or ON, and 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 E1 of DLC1
or DLC2.
SST 09843±18020
(7) Check diagnostic trouble code.
Replace center airbag sensor assembly.
Using simulation method, reproduce mal-
function symptoms (See page RS±48).
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±85

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

Tc Terminal Circuit
CIRCUIT DESCRIPTION
By connecting terminals Tc and E1 of the DLC1 or DLC2, the center airbag sensor assembly is set in the diagnos-
tic trouble code output mode. The diagnostic trouble codes are displayed by the blinking of the SRS warning
light.
RS±98± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTING

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