code 32 LEXUS SC300 1991 Service Repair Manual

COMPONENTS
RS043±01
FRONT PASSENGER AIRBAG
ASSEMBLY REMOVAL AND
INSTALLATION
RS044±01
NOTICE:
wIf the wiring connector of the supplemental restraint
system is disconnected with the ignition switch at ON or
ACC, diagnostic trouble codes will be recorded.
w Never use airbag parts from another vehicle. When
replacing parts, replace with new parts.
RS±30±
SUPPLEMENTAL RESTRAINT SYSTEM FRONT PASSENGER AIRBAG ASSEMBLY
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COMPONENTS
RS045±01
FRONT AIRBAG SENSOR
REMOVAL AND INSTALLATION
RS046±01
NOTICE:
wIf the wiring connector of the supplemental restraint
system is disconnected with the ignition switch at ON or
ACC, diagnostic trouble codes will be recorded.
w Never use SRS parts from another vehicle. When
replacing parts, replace with new parts.
w Never reuse the sensor involved in a collision when the
SRS has deployed.
w Never repair a sensor in order to reuse it.
RS±42±
SUPPLEMENTAL RESTRAINT SYSTEM FRONT AIRBAG SENSOR
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1. DISCONNECT NEGATIVE (±) TERMINAL CABLE FROMBATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the ªLOCKº posi-
tion and the negative (±) terminal cable is disconnected
from the battery.
(See page RS±2)
2. REMOVE ENGINE UNDER COVER
(See page BO±12)
3. REMOVE FRONT AIRBAG SENSOR
(a) Disconnect the connector.
(b) Remove the bolt, the nut and the sensor.
4. INSTALL FRONT AIRBAG SENSOR
(a) Install the sensor with the arrow on the sensor facing toward the front of the vehicle.
Torque: 25 N Vm (260 kgf Vcm, 19 ft Vlbf)
NOTICE:
w Make sure the sensor is installed to the specified torque.
w If the sensor has been dropped, or there are cracks, dents
or other defects in the case, brackets or c onnector,
replace the sensor is removed, always replace the set bolt
and the nut with new one.
w The sensor set bolt and the nut have been anti±rust
treated. When the sensor is removed, always replace the
set bolt and the nut with new ones.
w After installation, shake the sensor to check that there is
no looseness.
w The front sensor is equipped with an electrical
connection check mechanism. Be sure to lock this
mechanism securely when connecting the connector. If
the connector is not securely locked, a malfunction code
will be detected by the diagnosis system.
w Check that the dimensions of the body where the front
airbag sensor is installed match those in the body
dimension drawings in the BODY section.
(The SRS may malfunction, or may not work, if the
dimensions of the sensor mount is not correct.)
5. INSTALL ENGINE UNDER COVER
6. CONNECT NEGATIVE (±) TERMINAL CABLE TO BATTERY
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SUPPLEMENTAL RESTRAINT SYSTEM FRONT AIRBAG SENSORRS±43
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TROUBLESHOOTING
 HOW TO PROCEED WITH 
 TROUBLESHOOTING RS±54 CUSTOMER PROBLEM ANALYSIS CHECK SHEET RS±58 DIAGNOSIS INSPECTION RS±59 SYMPTION SIMULATION RS±65 DIAGNOSTIC TROUBLE CODE MATRIX CHART RS±67 PROBLEM SYMPTOM CHART RS±67 CIRCUIT INSPECTION RS±68 DTC (Normal) RS±68 DTC 11 RS±70 DTC 12 RS±78 DTC 13 RS±85 DTC 14 RS±92 DTC 15 RS±97 DTC 22 RS±102 DTC 31 RS±108 DTC 53 RS±110 DTC 54 RS±115 SRS Warning Light System (Always Lit Up, when ignition switch is Lock position) RS±119 Tc Terminal Circuit RS±121
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SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTINGRS±53
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HOW TO PROCEED WITH TROUBLESHOOTING
Malfunction symptoms of the supplemental restraint system are difficult to confirm, so the diagnostic
trouble codes become the most important source of information when troubleshoot\
ing. Perform trouble-
shooting of the supplemental restraint system in accordance with the fol\
lowing procedure:
HINT: Do not disconnect the battery negative (±) terminal cable until st\
ep , Diagnostic Trouble Code
Check and Recording, has been completed.

CUSTOMER PROBLEM ANALYSIS
Using the CUSTOMER PROBLEM ANALYSIS CHECK SHEET (See page RS±58) for reference, ask the
customer in as much detail as possible about the problem.
WARNING LIGHT CHECK
Check the SRS warning light. If the light remains on, a malfunction is stored in the center airbag sensor,
assembly, so proceed to step . If the SRS warning light is not on, a malfunction has occurred in the SRS
warning light circuit, so perform troubleshooting for 22.
HINT: 22 is recorded when a malfunction occurs in the SRS warning light syst\
em.
If an open malfunction occurs in the SRS warning light system, the SRS w\
arning light does not light up,
so that until the malfunction is repaired, the diagnostic trouble codes (\
including 22) cannot be confirmed.
 DIAGNOSTIC TROUBLE CODE CHECK AND RECORDING
Check the di agnostic trouble codes and make a note of any malfunction codes which ar\
e output. If a normal
code is output, an abnormality in the power source circuit may have occurred\
, so perform troubleshooting
for source voltage in step .
If 22 is output, skip steps  and  and proceed to step .
 MALFUNCTION CODE CLEARANCE
Clear the malfunction code.
HINT: The malfunction code output in step  indicates that a malfunction has occurred in the circuit desig-
nated by the malfunction code, but does not indicate whether the malfunction \
is still occurring or whether
it was in the past.
Accordingly, it is necessary to find out the present condition of the malfunction oc\
currence by clearing the
malfunction code and performing the diagnostic code check again. If this\
operation is neglected and trou-
bleshooting is performed using only the malfunction code confirmed in step , isolating the problem com-
ponent becomes difficult and invites mistaken diagnosis.
 DIAGNOSTIC TROUBLE CODE CHECK AND RECORDING  SYMPTOM SIMULATION
After repeating ignition switch ON±OFF operation (ON: wait 20 secs, OFF: \
wait 20 secs.) 5 times, check
the diagnostic trouble codes. If any code is output, the malfunction is sti\
ll occurring, so proceed to step .
Bearing in mind that a malfunction code was registered in step , provided that the normal code is present-
ly output, use the methods described in step  to simulate the malfunction.
RS±54
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SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTING
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NOTICE: When connecting the battery after clearing the malfunction code, always\
do it with the igni-
tion switch in LOCK position. When the battery has been reconnected, turn the ignition switch to
ACC or ON position after at least 2 seconds have elapsed.
If the battery is reconnected with the ignition switch in ACC or ON posi\
tion, or the ignition switch
is turned to ACC or ON within 2 seconds of connecting the battery, it is possible that the diagnosis
system will not operate normally.
 DIAGNOSTIC TROUBLE CODE CHART
Proceed to the appropriate flow chart in step  in accordance with the malfunction code found in step 
or .
 CIRCUIT INSPECTION \b REPAIR
Find out if the problem lies in a sensor, actuator or TROUBLESHOOTING, and repair the problem. After
the problem part is repaired, reinstall the disassembled parts. Do not s\
tart work until at least 90 seconds
after the ignition switch is turned to the LOCK position and the negative (±\
) terminal cable is disconnected.
CAUTION: If incorrect procedure is used, a malfunction may occur in the system o\
r there is the dan-
ger that airbag may be accidentally deploy during the repair operation. \
Carefully read the GENERAL
DESCRIPTION (See page RS±2) and the cautions for each operation, and perform repairs in the cor-
rect order using the correct methods.
HINT: The following illustration for the CIRCUIT INSPECTION shows each conne\
ctor for the SRS squib
circuit.
 
















 
















 
















±
SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTINGRS±55
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10 MALFUNCTION CODE CLEARANCEWhen all the malfunction codes found in steps  and  have been repaired, clear the malfunction codes.
11 DIAGNOSTIC TROUBLE CODE CHECK
After repeating ignition switch ON±OFF operation (ON: wait 20 secs, OFF: \
wait 20 secs.) 5 times, check
the diagnostic trouble codes. If a code is displayed, return to step  and troubleshoot the displayed mal-
function code.
NOTICE: When connecting the battery after clearing the malfunction code, always\
do it with the igni-
tion switch in LOCK position. When the battery has been reconnected, turn the ignition switch to
ACC or ON position after at least 20 seconds have elapsed.
If the battery is reconnected with the ignition switch in ACC or ON posi\
tion, or the ignition switch
is turned ACC or ON within 20 seconds of connecting the battery, it is possible that the diagnosis
system will not operate normally.
12 CONFIRMATION TEST Check the warning light again and confirm that all the malfunctions have been\
repaired. If the warning light
indicates an abnormality, repeat the operation again from step .
RS±56
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SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTING
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SRS WARNING LIGHT CHECK
DIAGNOSIS INSPECTION
(a) Turn the ignition switch to ACC or ON and check that the SRSwarning light lights up.
(b) Check that the SRS warning light goes out after approx. 6
seconds.
HINT:
wWhen the ignition switch is at ACC or ON and the SRS
warning light remains on, the TROUBLESHOOTING
has detected a malfunction code.
w If, after approx. 6 seconds have elapsed, the SRS
warning light sometimes lights up or the SRS warning
light lights up even when the ignition switch is OFF, a
short in the SRS warning light circuit can be considered
likely. Proceed to SRS warning light system (always lit
up when ignition switch LOCK position) on page
RS±119 .
DIAGNOSTIC TROUBLE CODE CHECK
Using diagnosis check wire:
1. OUTPUT DIAGNOSTIC TROUBLE CODE
(a) Turn the ignition switch to ACC or ON position and wait approx. 20 seconds.
(b) Using SST, connect terminals Tc and E of the DLC2. SST 09843±18020
NOTICE: Never make a mistake with the terminal connec-
tion position as this will cause a malfunction.
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SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTINGRS±59
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2. READ DIAGNOSTIC TROUBLE CODERead the 2±digit diagnostic trouble code as indicated by the
number of times the SRS warning light blinks. As an example,
the blinking patterns; normal, 11 and 31 are as shown on the
illustration.
wNormal code indication
The light will blink 2 times per second.
w Malfunction code indication
In the event of a malfunction, the light will blink. The number
represented by the first blink code output indicates the first
digit of a 2±digit diagnostic trouble code. After a 1.5 second
pause, the second blink code will indicate the second digit.
If there are two or more codes, there will be a 2.5 second
pause between each.
After all the codes have been output, there will be a 4.0 se-
cond pause and they will all be repeated.
HINT:
w In the event of a number of trouble codes, indication will
begin from the smaller numbered code to the larger.
w If it does not output a diagnostic trouble code or output
a diagnostic trouble code without terminal connection,
proceed to the Tc terminal circuit inspection on page
RS±121 .
Using LEXUS hand±held tester: (a) Hook up the LEXUS hand±held tester to the DLC1 or DLC2.
(b) Read the diagnostic trouble codes by following the prompts on the tester screen.
HINT: Please refer to the LEXUS hand±held tester operator's
manual for further details.
RS±60
±
SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTING
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DIAGNOSTIC TROUBLE CODES
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SUPPLEMENTAL RESTRAINT SYSTEM TROUBLESHOOTINGRS±61
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