Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Problem symptoms table
Toyota Corolla (E120): Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the table below. Use this table to troubleshoot the problem when a normal code is displayed in the diagnostic trouble code chart but the problem is still occurring. Numbers in the table indicate the order in which the circuits or parts should be checked.
Hint: when the problem is not detected by the diagnostic system even though the problem symptom is present, it may be that the problem is occurring outside the detection range of the diagnostic system.

Other materials:
Emission inspection and maintenance (I/M) programs
Some states have vehicle
emission inspection programs
which include OBD
(On Board Diagnostics)
checks. The OBD system
monitors the operation of
the emission control system.
If the malfunction indicator
lamp comes on
The OBD system determines
that a problem exists somewhere
in the emission control
sy ...
Engine
On–vehicle inspection
Hint:
inspect these items on a cooled down engine.
1. Inspect drive belt
2. Replace spark plugs
3. Inspect air filter
Remove the air filter.
visually check that the air filter is not excessively damaged,
dirty or oily.
Peplace the air filter if nece ...
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 ...


