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 throttle position sensor is mounted in the throttle body and
detects the throttle valve opening angle.
When the throttle valve is fully closed, a voltage of approximately
0.3 To 1.0 V is applied to terminal vta of the ecm. The voltage
applied to terminal vta of the ecm increases in pro ...
Cleaning and protecting the vehicle interior
Perform cleaning in a manner
appropriate to each
component and its material.
Protecting the vehicle
interior
Remove dirt and dust using a
vacuum cleaner. Wipe dirty
surfaces with a cloth dampened
with lukewarm water.
If dirt cannot be removed,
wipe it off with a soft cloth
dampened with neut ...
Communication system
Horn system
Location
Problem symptoms table
Inspection
1. Inspect low pitched horn assy
Connect the positive (+) lead from the battery to the terminal
and the negative (–) lead to the horn body, and check
that the horn blows.
If the result is not as specified, replace the ...


