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

Inspection procedure

    Share this page:

    Other materials:

    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 connectors between the horn button assy and the airbag sensor assy center.  for the blac ...

    On–vehicle inspection
    1. Inspection throttle body idle speed control valve assy Notice: it is impossible to check the resister value and the operation of isc valve by itself, because the isc valve has an ic circuit inside it, which transforms the duty signal from the ecm to the derive signal. After check ...

    Removal and installation of fuel control parts
    Place for removing and installing of fuel system parts  work in a place with good air ventilation and without anything flammable such as welder, grinder, drill, electric motor or stove in the surroundings.  Never work in a place such as a pit or nearby a pit, as there is a ...