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:
Abbreviations used in this manual
...
Inspection procedure
1 Inspect transmission wire(sl)
Disconnect the transmission wire connector from the
transaxle.
measure the resistance according to the value(s) in the
table below.
Standard:
2 Check harness and connector(transmission wire – ecm)
Connect the transmission wire c ...
Warning buzzer does not sound (key reminder
warning, light reminder warning)
Wiring diagram
Inspection procedere
1 Check buzzer
Check that all of the warning buzzers sound.
2 Inspect front door courtesy lamp switch assy
3 Inspect un–lock warning switch assy
4 Check harness and connector(between un–lock warning switch
and combination meter as ...


