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 side squib(rh) circuit(airbag sensor assy center – front
seat airbag assy rh)
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 ...
Correct driving posture
1 Adjust the angle of the seatback so that you are sitting straight up and so
that you do not have to lean forward to steer.
2 Adjust the seat so that you can depress the pedals fully and so that your arms
bend slightly at the elbow when gripping the steering wheel.
3 Lock the head restraint ...
Circuit description
Refer to dtc p0130
Dtc no.
Dtc detection condition
Trouble area
P0133
After engine has been warmed up, if response time that heated
oxygen sensor’s output voltage reaches from rich to lean.
Or from lean to rich, is 0.6 Second or more during idling.
...


