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 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 ...
Dtc check/clear
1. Dtc check (normal mode)
Notice:
hand–held tester only:
when the diagnostic system is switched from the normal
mode to the check mode, all the dtcs and freeze frame
data recorded in the normal mode will be erased. So before
switching modes, always check the dtcs and freeze frame
data, and ...
Overhaul
Caution:
wear the gloves, because the cutting surface of the seat back frame and seat
adjuster may injure
your hand.
Hint:
tape the screwdriver tip before use when prying parts.
1. Disconnect battery negative terminal
Caution:
wait for 90 seconds after disconnecting the battery terminal a ...


