1991 LEXUS SC400 Service Repair Manual

Page 3097 of 4087

LEXUS SC400 1991  Service Repair Manual 
WIRING DIAGRAM
SRS Warning Light System (Always Lit Up, when ignition switch in
LOCK position)
CIRCUIT DESCRIPTION
The SRS warning light is located on the combination meter.
When the supplemental res

Page 3098 of 4087

LEXUS SC400 1991  Service Repair Manual 
YESNO
INSPECTION PROCEDURE
1Does SRS warning light turn off?
C
Hint
P1. Turn ignition switch LOCK.
2. Disconnect  negative (±) terminal cable from battery
and wait at least 90 seconds.
3. Remove ste

Page 3099 of 4087

LEXUS SC400 1991  Service Repair Manual 
Tc Terminal Circuit
CIRCUIT DESCRIPTION
By connecting terminal Tc and E1 of the DLC1 or DLC2, the center airbag sensor assembly is set in the di\
agnos-
tic trouble code output mode. The diagnostic t

Page 3100 of 4087

LEXUS SC400 1991  Service Repair Manual 
WIRING DIAGRAM
DIAGNOSTIC CHARTDIAGNOSTIC CHART
RS±122±
SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTING 
WhereEverybodyKnowsYourName

Page 3101 of 4087

LEXUS SC400 1991  Service Repair Manual 
NGOK
NGOK
INSPECTION PROCEDURE
HINT: If the diagnostic trouble code is not displayed, perform the following \
troubleshooting:
1Check voltage between terminals Tc and E1 of DLC1 or DLC2.
C
OK
PTurn i

Page 3102 of 4087

LEXUS SC400 1991  Service Repair Manual 
NGOK
3Check center airbag sensor assembly.
C
OK
P1. Turn ignition switch LOCK.
2. Disconnect  battery negative (±) terminal cable, andwait at least 90 seconds.
3. Remove steering wheel pad (See page

Page 3103 of 4087

LEXUS SC400 1991  Service Repair Manual 
NGOK
HINT: If the diagnostic trouble code is continuously displayed, perform the f\
ollowing troubleshooting.
1Check resistance between terminal Tc of center airbag sensor assembly and body ground.
C

Page 3104 of 4087

LEXUS SC400 1991  Service Repair Manual 
SERVICE SPECIFICATIONS
SERVICE DATA
RS02S±01
\
 \
FRONT AIRBAG SENSOR\
 \

\
 \
S ±