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:
Audio & visual system
Preparation
Sst
Recomended tools
Equipment
...
Engine (ignition) switch (vehicles
with a smart key system)
Performing the following
operations when carrying
the electronic key on your
person starts the engine or
changes engine switch
modes.
Starting the engine
1. Check that the parking brake
is set.
2. Check that the shift lever is in
P.
3. Firmly depress the brake
pedal.
and a message will be display ...
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 ...