Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Customer problem analysis
Toyota Corolla (E120): Customer problem analysis
Hint
:
- in troubleshooting, the problem symptoms must be confirmed accurately, meaning that all preconceptions must be set aside in order to make an accurate judgement. To ascertain what the problem symptoms are, it is extremely important to ask the customer about the problem and conditions when it occurred.
- The following 5 items are important points in the problem analysis. Past problems which are thought to be unrelated and the repair history, etc. May also help in some cases. Therefore, as much information as possible should be gathered and its relationship with the problem symptoms should be correctly ascertained for use as reference in troubleshooting. A customer problem analysis table is provided for your use in the diagnostics section for each system.

(Sample) supplemental restraint system check sheet.

Other materials:
Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the
table below. Use this table to
troubleshoot the problem when a normal code is displayed in the diagnostic
trouble code chart but the problem
is still occurring. Numbers in the table indicate the order in which the
circ ...
Driving support system
information display
■ Driving support system
information
Select to display the operational
status of the following systems:
Dynamic radar cruise control
LTA (Lane Tracing Assist)
LDA (Lane Departure Alert)
■ Navigation system-linked
display (if equipped)
Select to display the following
navigation system-linked ...
Seat belt warning lamp for driver’s seat does not
operate
Wiring diagram
Inspection procedure
1 Check combination meter assy
Ground terminal c9–12 on the combination meter side.
check that the warning lightlights up.
Ok: warning light lights up.
2 Inspect front seat inner belt assy lh
Disconnect the front seat inner belt ...


