IN04T-22
Vehicle Brought to Workshop
Customer Problem
Analysis
Symptom Confirmation
and Diagnostic Trouble
Code Check
Symptom Simulation
Diagnostic Trouble
Code Chart
Problem Symptoms Table
Circuit Inspection or Parts
Inspection
Repair
Confirmation Test
End
1
2
4
3
5
6
7
8
Ask the customer about the conditions and the
environment in which the problem occurred.
1
Confirm the symptoms and the problem conditions,
and check the diagnostic trouble codes.
(When the problem symptoms do not appear
during confirmation, use the symptom simulation
method described later on.)
2, 3
Check the results obtained in Step 2. Confirm
the inspection procedure for the system or the part
that should be checked using the diagnostic
trouble code chart or the problem symptoms table.
4, 5, 6
Check and repair the affected system or part in
accordance with the instructions in Step 6.
7
After completing repairs, confirm that the problem
has been eliminated.
(To be absolutely sure the problem no longer ex-
ists, perform the confirmation test under the same
conditions and environment as when it occurred
the first time.)
8
IN-22
-
INTRODUCTION
HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
22
Author:
Date:
2005 LEXUS IS300 (RM1140U)
HOW TO PROCEED WITH TROUBLESHOOTING
Carry out troubleshooting in accordance with the procedure below. Only a basic procedure is shown. Details
in the Diagnostics section show the most effective methods for each circuit. Confirm troubleshooting proce-
dures first for the relevant circuit before beginning troubleshooting of that circuit.
