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:
Circuit description
Refer to dtc p0130
Hint:
the ecm provides a pulse width modulated control circuit to adjust current
through the heater. The heated
oxygen sensor heater circuit uses a relay on the b+ side of the circuit.
Monitor description
The ecm uses the heated oxygen sensor information to regulate t ...
Content of driving information
■ Display items
Fuel economy
Eco Driving Indicator/Driving
range
■ Fuel economy
Use the displayed values as a reference
only.
Current fuel consumption
Displays instantaneous current fuel
consumption.
Average fuel economy (after
reset)
To reset the average fuel economy
display, press ...
Standard bolt
How to determine bolt strength
Specified torque for standard bolts
How to determine nut strength
*: Nut with 1 or more marks on one side surface of the nut.
Hint:
use the nut with the same number of the nut strength classification or the
greater than the bolt strength classificati ...


