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:
Circuit description
This circuit turns on the magnetic clutch inside the actuator during cruise
control operation according to the
signal from the ecu. If a malfunction occurs in the actuator or speed sensor,
etc. During cruise control operation,
the rotor shaft between the motor and control plate is released.
...
Purpose of the readiness tests
The on–board diagnostic (obd ii) system is designed to monitor the
performance of emission–related
components and report any detected abnormalities in the form of diagnostic
trouble codes
(dtcs). Since the various components need to be monitored during different
driving condition ...
Replacement
Hint: components:
1. Remove radiator grille sub–assy
2. Remove front bumper cover
3. Remove lh headlamp assy
Remove the 3 bolts.
pull out the headlight assy lh forward, then disconnect
the bracket of body side.
Release the claws and disconnect the connectors as
sh ...


