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
Hint:
read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, it is
useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, the ...
If the electronic key does not
operate properly (vehicles with a
smart key system)
If communication between
the electronic key and vehicle
is interrupted or the electronic key cannot
be used because the battery
is depleted, the smart key
system and wireless remote
control cannot be used. In
such cases, the doors can
be opened and the engine
can be started by following
the procedur ...
Steering wheel audio switches
Some audio features can be controlled using the switches on the steering wheel.
Operation may differ depending on the type of audio system or navigation system.
For details, refer to the manual provided with the audio system or navigation system.
Operating the audio system using the steering whe ...


