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 operation(stop lamp swtich assy)
Check that the stop light comes on when the brake pedal is depressed,
and turns off when the brake
pedal is released.
2 Input signal check
See input signal check on page 05–745.
check the indicator light when the brake pedal ...
Battery
Check the battery as follows.
■ Battery exterior
Make sure that the battery terminals are not corroded and that there are no
loose connections, cracks, or loose clamps.
1 Terminals
2 Hold-down clamp
■Before recharging
When recharging, the battery produces hydrogen gas which is ...
Circuit description
The throttle pressure that is applied to the primary regulator
valve (which modulates the line pressure) causes the solenoid
valve slt, under electronic control, to precisely and minutely
modulate and generate the line pressure according the extent
of the accelerator pedal depressed or the o ...


