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:
Overhaul
Hint: components:
1. Discharge refrigerant from refrigeration system
sst 07110–58060 (07117–58080, 07117–58090, 07117–78050, 07117–88060,
07117–88070,
07117–88080)
2. Disconnect cooler refrigerant liquid pipe a
Remove the bolt and disconnect the cooler refrigerant liqui ...
Inspection procedure
1 Inspect dlc3 terminal voltage
Turn the ignition switch to on.
measure voltage between terminals 13 (tc) and 4 (cg) of
dlc3.
Ok:
voltage: 10 – 16 v
2 Check harness and connector(between cruise control ecu assy
and dlc3)
Check for open and short circuit in harness ...
Inspection procedure
Hint:
read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, it is
useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, the ...


