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:
Key information
Keys
The following keys are provided with the vehicle.
► Vehicles without a smart key system
(type A)
1 Keys
2 Key number plate
► Vehicles without a smart key system (type
B)
1 Keys
Operating the wireless remote control function
2 Key number plate
► Vehicles ...
Circuit description
Refer to dtc p0115
Dtc no.
Dtc detection condition
Trouble area
P0125
If the engine coolant temperature (ect) was less than –6.6 °C
(20 °F) when starting the engine, and 20 minutes after the engine
start, the ect sensor still indicates below 20 °C (68 ...
Heater control & accessory assy
Replacement
1. Remove console panel upper
2. Remove instrument cluster finish panel
3. Remove heater control & accessory assy
Release the 2 fitting claws and pull out the heater control
& accessory assy.
Using a screwdriver, open the claw of the cable clamp and
dis ...


