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:
Driving support system
information display
■ Driving support system
information
Select to display the operational
status of the following systems:
LTA (Lane Tracing Assist)
LDA (Lane Departure Alertl)
Dynamic radar cruise control
■ Navigation system-linked
display (if equipped)
Select to display the following
navigation system-linke ...
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished). Perform active test using
hand–held tester (a/f
control).
Perform active test using the hand–held ...
Riding with children
Observe the following precautions
when children are
in the vehicle.
Use a child restraint system
appropriate for the child,
until the child becomes
large enough to properly
wear the vehicle's seat belt.
It is recommended that children
sit in the rear seats to
avoid accidental contact
with the ...


