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:
Inspection procedure
1 Check p squib circuit(airbag sensor assy center – instrument
panel passenger airbag assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the instrument panel ...
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).
Hint:
”a/f control” is the act ...
Setting the tire pressure
(vehicles with a tire pressure
warning system)
In the following situations, it will
be necessary to perform the tire
inflation pressure setting procedure
of the tire pressure warning
system.
When the specified tire inflation
pressure has changed,
such as due to carried load,
etc.
When the tire inflation pressure
is changed such as
when t ...


