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:
Evap monitor (vacuum pressure monitor)
Notice:
a cold soak must be performed prior to conducting the drive pattern to complete
the internal pressure
readiness monitor.
Cold soak preconditions
The monitor will not run unless:
mil is off.
Fuel level is approximately 1/2 to 3/4.
Altitude is 7800 feet (2400 m) or less.
...
Inspection procedure
1 Check d squib circuit(airbag sensor assy center – horn button
assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connector between the airbag sensor
assy center and the horn button assy.
for the black ...
Circuit description
The throttle pressure that is applied to the primary regulator
valve (which modulates the line pressure) causes the solenoid
valve slt, under electronic control, to precisely and minutely
modulate and generate the line pressure according the extent
of the accelerator pedal depressed or the o ...