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:

    Displaying the device status
    Select “Bluetooth* info” using . ● Displaying the device name Select “Device Name” using . ● Displaying the device address Select “Device Address” using . *: Bluetooth is a registered trademark of Bluetooth SIG, Inc. ...

    Symptom confirmation and diagnostic trouble code
    Hint: the diagnostic system in corolla has various functions. The first function is the diagnostic trouble code (dtc) check, in which a malfunction in the signal circuits to the ecu is stored in code form in the ecu memory. Another function is the input signal check, which checks if ...

    Warning lights and indicators
    The warning lights and indicators on the instrument cluster, center panel, overhead console and outside rear view mirrors inform the driver of the status of the vehicle's various systems. Warning lights and indicators displayed on the instrument cluster For the purpose of explanation, the followin ...