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:
Initialization
1. Reset memory
Caution:
perform the reset memory (at initialization) when replacing the automatic
transaxle assy, engine
assy or ecm.
Notice:
hand–held tester only
Turn the ignition switch off.
connect the hand–held tester to the dlc3.
turn the ignition switch to th ...
Problem symptoms table
Hint:
if a normal code is displayed during the dtc check but the trouble still occurs,
check the circuits for each
symptom in the order given in the charts on the following pages and proceed to
the page given for troubleshooting.
The matrix chart is divided into 3 chapters.
If the instruc ...
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct procedure
as given in these sections.
CAUTION
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energized. To avoid death or serious injury,
observe t ...


