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:
Changing engine switch modes
Modes can be changed by pressing the engine switch with the brake pedal (continuously
variable transmission) or clutch pedal (manual transmission) released. (The mode
changes each time the switch is pressed.)
► Vehicles without a multi-information display
Off*
The emergency flashers ca ...
Diagnostic trouble code chart
If a dtc is displayed during the dtc check, check the circuit listed in the
table below and proceed to the
page given.
* :● ... Mil light up
...
Overhaul
Hint: components:
1. Discharge refrigerant from refrigeration system
sst 07110–58060 (07117–58080, 07117–58090, 07117–78050, 07117–88060,
07117–88070,
07117–88080)
2. Disconnect cooler refrigerant liquid pipe a
Remove the bolt and disconnect the cooler refrigerant liqui ...


