Lexus SC300 / Lexus SC400. Manual - part 790

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 position, 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

CIRCUIT INSPECTION

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 start 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 or 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 connector for the SRS squib
circuit.

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SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING

RS–55

10 MALFUNCTION CODE CLEARANCE

When 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 position, 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

–

SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING

–

SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING

RS–57

CUSTOMER PROBLEM ANALYSIS CHECK SHEET

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Supplemental Restraint System Check Sheet

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Inspector’s
Name

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C stomer’s Name

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Registration No.

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Customer’s Name

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Registration Year

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/ /

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===========

Frame No.

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Date Vehicle
B

ht I

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Odometer Reading

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Brought In

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/ /

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Odometer Reading

Miles

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Date Problem First Occurred

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/ /

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Weather

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Fine

Cloudy

Rainy

Snowy

Other______________

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Temperature

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Approx.

C (

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Vehicle Operation

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Starting

Idling

Driving

Constant speed

Acceleration

Deceleration

other ]

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Road Conditions

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Details of Problem

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Details of Problem

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Vehicle Inspection, Repair History Prior
to Occurrence of Malfunction (Includ-
ing Supplemental Restraint System)

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Diagnosis System Inspection

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SRS Warning Light

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1st Time

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Remains ON

Sometimes Lights Up

Does Not Light Up

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SRS Warning Light
Inspection

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2nd Time

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Remains ON

Sometimes Lights Up

Does not Light Up

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Diagnostic Trouble

1st Time

Normal Code

Malfunction Code [Code.

]

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Diagnostic Trouble
Code Inspection

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2nd Time

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Normal Code

Malfunction Code [Code.

]

RS–58

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SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING

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