Toyota Corolla (E120): Circuit description

When the ignition switch is turned on, battery positive voltage is applied to the coilwhich closes the contacts of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.

This signal causes current to flow to the coil, closing the contacts of the efi relay and supplying power to terminal +b of the ecm.

If the ignition switch is turned off, the ecm continues to switch on the efi relay for a maximum of 2 seconds for the initial setting of the isc valve.

Wiring diagram

Inspection procedure

    Share this page:

    Other materials:

    Check and replace ecu
    Notice: start an inspection of the connector from the backside of the connector on the wire harness side with the connector connected to the ecu. When no measurement condition is specified, perform the inspection with the engine stopped and also the ignition switch on. First check the ec ...

    Circuit description
    The throttle position sensor is mounted in the throttle body and detects the throttle valve opening angle. When the throttle valve is fully closed, a voltage of approximately 0.3 To 1.0 V is applied to terminal vta of the ecm. The voltage applied to terminal vta of the ecm increases in pro ...

    Alarm
    The alarm uses light and sound to give an alert when an intrusion is detected. The alarm is triggered in the following situations when the alarm is set: A locked door or trunk is unlocked or opened in any way other than using the entry function (if equipped), wireless remote control, mechani ...