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:
Key information
Keys
The following keys are provided with the vehicle.
► Vehicles without a smart key system
(type A)
1 Keys
2 Key number plate
► Vehicles without a smart key system (type
B)
1 Keys
Operating the wireless remote control function
2 Key number plate
► Vehicles ...
Circuit description
The purpose of this circuit is to prevent the engine from stalling while
driving in lock–up condition, when
brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signals to the ecm. Then
the ecm cancels the operation
of the lock–up clutch while braking is i ...
How to proceed with troubleshooting
Hint:
carry out troubleshooting in accordance with the procedures on the following
page. Here, only the basic
procedures are shown. Details are provided in the diagnostics section, showing
the most effective methods
for each circuit. Confirm the troubleshooting procedures first for the releva ...


