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:
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown.
If this happens, check and replace the fuses as necessary.
1 Turn the engine switch off.
2 Open the fuse box cover.
► Engine compartment
Push the tab in and lift the lid off.
► Under the driver’s side i ...
Mass or volume air flow circuit
Dtc p0100 mass or volume air flow circuit
Dtc p0102 mass or volume air flow circuit
low input
Dtc p0103 mass or volume air flow circuit
high input
Circuit description
The maf (mass air flow) sensor measures the amount of air flowing through the
throttle valve. The ecm
uses this information ...
Air outlets
■ Location of air outlets
The air outlets and air volume changes according to the selected airflow mode.
: Some models
■ Adjusting the position of and opening and closing the air outlets
► Front center outlets
Direct air flow to the left or right, up or down.
► Fro ...


