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 p/t squib(lh) circuit(airbag sensor assy center – front seat
outer belt 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 seat belt pretensio ...
Overhaul
Caution:
wear the gloves, because the cutting surface of the seat back frame and seat
adjuster may injure
your hand.
Hint:
tape the screwdriver tip before use when prying parts.
1. Disconnect battery negative terminal
Caution:
wait for 90 seconds after disconnecting the battery terminal a ...
Inspection procedure
Hint:
if different dtcs related to different systems that have terminal e2
as the ground terminal are output
simultaneously, terminal e2 may be open.
Read freeze frame data using the hand-held tester or the obd ii scan
tool. Freeze frame data records
the engine conditions when a malf ...


