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:
General information
There are many ecu controlled systems used in the corolla. In general, ecu
controlled system are considered
to be very intricate and require a high level of technical knowledge and expert
skill to troubleshoot.
The fact is, however, that if you proceed by inspecting the circuits one by one, ...
Circuit description
The vapor pressure sensor and the vsv for the canister closed valve (ccv) are
used to detect abnormalities
in the evaporative emission control system. The ecm decides whether there is an
abnormality in the evaporative
emission control system based on the vapor pressure sensor signal.
Dtc p0 ...
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 ...


