1991 LEXUS SC300 Service Repair Manual

Page 257 of 4087

LEXUS SC300 1991  Service Repair Manual 
DIAGNOSTIC CHART (Contd)
Check front airbag sensor.Replace front airbag sensor.
Repair or replace spiral cable.Check spiral cable. Repair or replace harness or connector
between center airbag sensor

Page 258 of 4087

LEXUS SC300 1991  Service Repair Manual 
(1) Disconnect  battery negative (±) terminal cable,and wait at least 20 seconds.
(2) Remove steering wheel pad (See page  AB±16).
Check front airbag sensor circuit. (Measure resistance between ter

Page 259 of 4087

LEXUS SC300 1991  Service Repair Manual 
(1) Connect  connector to center airbag sensorassembly.
(2) Using a service wire, connect D
+, D± on spiral
cable side of connector between spiral cable
and steering wheel pad.
(3) Connect negative

Page 260 of 4087

LEXUS SC300 1991  Service Repair Manual 
(1) Turn ignition switch LOCK.
(2) Disconnect  battery negative (±) terminal cable,and wait at least 20 seconds.
(3) Connect  steering wheel pad (squib) connector.
(4) Connect  negative (±) termina

Page 261 of 4087

LEXUS SC300 1991  Service Repair Manual 
Check squib circuit.
Disconnect  connector between center airbag sen-
sor assembly and spiral cable.
Measure resistance between D+, D± on spiral
cable side of connector between spiral cable and
stee

Page 262 of 4087

LEXUS SC300 1991  Service Repair Manual 
Diag. Code 12Short in Squib Circuit or Front Airbag
Sensor Circuit (to +B)
CIRCUIT DESCRIPTION
The squib circuit consists of the center airbag sensor assembly, spiral cable and the steering wheel
pad

Page 263 of 4087

LEXUS SC300 1991  Service Repair Manual 
DIAGNOSTIC CHART
Preparation.
Check front airbag sensor circuit.
(Measure voltage between terminal +SR
or +SL of center airbag sensor assembly
connector and body ground).
From the results of the abov

Page 264 of 4087

LEXUS SC300 1991  Service Repair Manual 
(1) Disconnect  battery negative (±) terminal cable,and wait at least 20 seconds.
(2) Remove steering wheel pad (See page  AB±14).
Check front airbag sensor circuit. (Measure resistance between ter