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
1. Drain brake fluid
Notice:
wash the brake fluid off immediately if it comes into contact with any painted
surface.
2. Remove air cleaner cap sub–assy
3. Remove brake master cylinder sub–assy
disconnect the brake fluid level switch connector from
master cylinder reservoir subâ ...
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 ...
Circuit description
The rotary solenoid type idle air control (iac) valve is located
under the throttle body and intake air bypassing the throttle
valve flows into the iac valve through the passage.
In this way the intake air volume bypassing the throttle valve is
regulated, controls the engine speed.
The ...