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:
Unlocking and locking the doors from the outside
◆ Smart key system (if equipped)
Carry the electronic key to enable this function.
1 Grip the driver’s door handle to unlock the door. Grip the passenger’s door
handle to unlock all the doors.* Make sure to touch the sensor on the back of the
handle.
The doors cannot be unlocked for ...
Warning lights
Warning lights inform the driver of malfunctions in the indicated vehicle’s systems.
*1: Vehicles without a smart key system:
These lights turn on when the engine switch is turned to the “ON” position to indicate
that a system check is being performed. They will turn off after the engi ...
Removal and installation of fuel control parts
Place for removing and installing of fuel system parts
work in a place with good air ventilation and without anything
flammable such as welder, grinder,
drill, electric motor or stove in the surroundings.
Never work in a place such as a pit or nearby a pit, as there is a ...


