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:

    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 ...

    Doors
    Unlocking and locking the doors from the outside ■ Smart key system (if equipped) Carry the electronic key to enable this function. Grip the driver's door handle to unlock the door. Holding the driver's door handle for approximately 2 seconds unlocks all the doors. Grip the front passenger ...

    Child restraint system fixed with a seat belt
    A child restraint system for a small child or baby must itself be properly restrained on the seat with the lap portion of the lap/shoulder belt. ■ Installing child restraint system using a seat belt (child restraint lock function belt) Install the child restraint system in accordance to the operat ...