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
1 Check p squib circuit(airbag sensor assy center – instrument
panel passenger airbag assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the instrument panel ...
On–vehicle inspection
1. Check cooling fan operation with low temperature (below 83 c (181 f))
Turn the ignition switch on.
check that the cooling fan stops.
Hint:
if not, check the cooling fan relay and water temperature sensor, and check for
separated connector or severed
wire between the cooling fan ...
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished).
Perform active test using hand–held tester (a/f control).
Hint:
”a/f control” is the active te ...