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:
Inspection procedure
1 Check side squib(rh) circuit(airbag sensor assy center – front
seat airbag assy rh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the front seat airbag
assy (rh) and the airbag sensor assy center. ...
Pressing power switch does not start system
Wiring diagram
Inspection procedure
1 Inspect radio receiver assy(+b, acc, gnd)
Check that the continuity between terminals at each
condition, as shown in the chart.
Standard:
Check that the voltage between terminals at each condition,
as shown in the chart.
Standard:
...
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 ...


