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:
What to do if... (Troubleshooting)
If you have a problem, check the following before contacting your Toyota dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
● If you lose your keys or mechanical keys, new genuine keys or mechanical keys
can be made by your Toyota dealer.
● If you lo ...
Checking the messages
1 Display the “Message Inbox” screen.
2 Select the desired message from the list.
3 Check that the message is displayed.
1 E-mails: Select “Mark Unread” or “Mark Read” to mark mail unread or read on
the message inbox screen.
This function is available when “Update Message Read S ...
Content of driving information
■ Display items
Speedometer display/Driving
range
Fuel economy
Eco Driving Indicator/Driving
range
■ Speedometer display/Driving
range
Speedometer display
Driving range
Displays driving range with remaining
fuel. Use the displayed values
as a reference only.
This distance is computed ...


