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:
Lubrication system
*: The engine oil capacity is a reference quantity to be used when changing the
engine oil. Warm up and turn off the engine, wait more than 5 minutes, and check
the oil level on the dipstick.
■ Engine oil selection
“Toyota Genuine Motor Oil” is used in your Toyota vehicle. Use Toyo ...
For vehicles equipped with mobile communication system
Install an antenna as far as possible away from the ecu
and sensors of the vehicle’s electronic systems.
install an antenna feeder at least 20 cm (7.87 In.) Away
from the ecu and sensors of the vehicle’s electronic systems.
For details of the ecu and sensors locations, refer ...
Circuit description
A flat type knock sensor (non–resonant type) has the structure that can
detect the vibration in a wider band
of frequency from about 6 khz to 15 khz and has the following features.
Knock sensors are fitted on the cylinder block to detect the engine knocking.
The sensor contains a piezoele ...


