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:
Circuit description
The o/d main switch (transmission control switch) is a momentary type switch.
When pressing the o/d main
switch, the o/d off indicator light lights up and the ecm prohibits shifting
into o/d, and when pressing it
once again, the o/d off indicator light goes off and the ecm allows shifting
in ...
Inspection procedure
Hint:
the switch described in this text is a switch for transmitting signals which is
built in the door control transmitter.
1 Check wireless door lock control functions
Normal
2 Replace transmitter battery with normal one
After replacing the transmitter battery with a new or normal o ...
Inspection procedure
1 Input signal check
See input signal check on page 05–745.
check indicator light operation when driving with vehicle
speed above 40 km/h (25 mph), and with vehicle speed
below 40 km/h (25 mph).
Ok:
vehicle speed above 40 km/h (25 mph):
indicator light blinks
vehicle speed be ...


