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:
Circuit description
The purpose of this circuit is to prevent the engine from stalling while
driving in lock–up condition, when
brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signals to the ecm. Then
the ecm cancels the operation
of the lock–up clutch while braking is i ...
Fog light switch
The fog lights secure excellent visibility in difficult driving conditions,
such as in rain and fog.
1 Turns the front fog lights off
2 Turns the front fog lights on
*1: For U.S.A.
*2: For Canada
■Fog lights can be used when
The headlights are on in low beam. ...
Fuel information
You must only use unleaded gasoline in your vehicle.
Select octane rating 87 (Research Octane Number 91) or higher.
Use of unleaded gasoline with an octane rating lower than 87 may result in engine
knocking. Persistent knocking can lead to engine damage.
At minimum, the gasoline you use should ...


