Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Circuit inspection
Toyota Corolla (E120): Circuit inspection
How to read and use each page is shown below.

Other materials:
Circuit description
The fuel trim is related to the feedback compensation value, not to the basic
injection time. The fuel trim includes
the short–term fuel trim and the long–term fuel trim.
The short–term fuel trim is the short–term fuel compensation used to maintain
the air–fuel ratio at stoichiomet ...
On–vehicle inspection
1. Connect hand–held tester:
connect the hand–held tester to the dlc3.
start the engine and run it at idle.
select the active test mode on the hand–held tester.
Hint:
please refer to the hand–held tester operator’s manual for further details.
2. Inspect actua ...
If a warning message is displayed
The multi-information display
shows warnings for
system malfunctions and
incorrectly performed operations,
and messages that
indicate a need for maintenance.
When a message is
displayed, perform the
appropriate corrective
action for the message.
If a warning message is displayed
again after the
ap ...


