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 ...
Inspection procedure
1 Check side squib(lh) circuit(airbag sensor assy center – front
seat airbag assy lh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the front seat airbag assy ...
Inspection procedure
1 Check side squib(lh) circuit(airbag sensor assy center – front
seat airbag assy lh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the front seat airbag assy ...


