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:
Diagnostics
Preparation
Sst
09816–30010
Oil pressure switch socket
Sfi system
09843–18040
Diagnosis check wire no.2
Sfi system
supplemental restraint
system
Recomended tools
09082–00040
Toyota electrical tester
Sfi system
supplemen ...
Inspection procedure
1 Input signal check
See input signal check on page 05–745.
check the indicator light operation when each of the set/
coast, resume/accel and cancel is turned on.
Ok:
set/coast, resume/accel switch:
the signals shown in the table on the left should be
output when each switch is ...
Circuit description
The intake air temperature (iat) sensor, mounted on the mass
air flow (maf) sensor, monitors the intake air temperature. The
iat sensor has a thermistor that varies its resistance depending
on the temperature of the intake air. When the air temperature
is low, the resistance in the thermisto ...


