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:
For vehicles equipped with srs airbag and seat belt pretensioner
Hint:
the vehicle is equipped with an srs (supplemental restraint system), such as the
horn button assembly,
the instrument panel passenger airbag assembly, the front seat airbag assembly,
the center airbag sensor
assembly, the front airbag sensor, the side airbag sensor and the seat belt
p ...
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished).
Perform active test using hand–held tester (a/f control).
Hint:
”a/f control” is the active te ...
Inspection procedure
1 Inspect terminal voltage(idl)
Remove the cruise control ecu assy with connector still
connected.
disconnect the ecm connector.
turn the ignition switch to on.
measure voltage between terminal 13 (idl) of cruise control
ecu assy connector and body ground when the ...


