Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Mil circuit / Circuit description
Toyota Corolla (E120): Circuit description
The ignition switch provides circuit power and the ecm provides the circuit ground that illuminates the mil.
Mil operation is checked visually: it should be illuminated when the ignition is first turned on. If the mil is off all of the time or on all of the time, use the procedure below to troubleshoot it. The mil is used to indicate the ecm’s detection of a vehicle malfunction.
Follow this procedure using the hand–held tester or an obd ii scan tool to determine the cause of the problem and to check the mil.
Wiring diagram

Other materials:
Automatic transaxle assy (atm)
Precaution
The automatic transaxle is composed of highly precision–finished
parts, necessitating careful
inspection before reassembly because even a small nick could cause fluid
leakage or affect
the performance. The instructions here are organized so that you work on
only o ...
Selecting wheel set (vehicles
with a tire pressure
warning system)
Your vehicle is equipped with a
tire pressure warning system
with a function to register two
sets of ID codes. This allows for
registration of a second wheel
set, for example a winter set.
The wheel set can be changed
only if a second wheel set has
been registered to the system. If
a second wheel s ...
Diagnostic trouble code chart
The inspection procedures are shown in the table below. This table allows
efficient and accurate troubleshooting
using the diagnostic trouble codes displayed in the diagnostic trouble code
chart. Proceed with
troubleshooting in accordance with the inspection procedures listed in the
diagnost ...


