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:
Switching the display
Press to display or hide the album
title.
If there is additional text, is
displayed.
Press and hold to display the remaining
text.
■USB memory functions
●Depending on the USB memory that is connected to the system, the device itself
may not be operable and certain function ...
Driving assist systems
To keep driving safety and
performance, the following
systems operate automatically
in response to various
driving situations. Be
aware, however, that these
systems are supplementary
and should not be relied
upon too heavily when operating
the vehicle.
Summary of the driving
assist systems
■ ABS ( ...
Circuit description
While driving uphill with cruise control activated, in order to minimize gear
shifting and provide smooth cruising
overdrive may be prohibited temporarily under some conditions.
The cruise control ecu sends o/d cut signals to the ecm as necessary and the ecm
cancels overdrive
shifting until ...


