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:
Shifting the shift lever to R
Shift the shift lever to R while lifting up the ring section.
■Maximum allowable speeds
Observe the following maximum allowable speeds in each gear when maximum acceleration
is necessary.
mph (km/h)
NOTICE
■To prevent damage to the transmission
●Do not lift up the ring ...
Inspection
1. Spark plug
Notice:
never use a wire brush for cleaning.
Never attempt to adjust the electrode gap on used
spark plug.
Spark plug should be replaced every 192,000 km
(120,000 miles).
Clean the spark plugs.
Air pressure: below 588 kpa (6.0 Kg/cm2, 85 psi)
duration: 20 sec ...
How to proceed with troubleshooting
1 Vehicle brought in
2 Customer problem analysis check and symptom check
3 Problem symptoms table
Without applicable symptoms, proceed to ”a”
with applicable symptoms, proceed to ”b”
4 Perform troubleshooting in the following method, depending on
malfunction symptom ...


