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:

    If you think something is wrong
    If you notice any of the following symptoms, your vehicle probably needs adjustment or repair. Contact your Toyota dealer as soon as possible. Visible symptoms ● Fluid leaks under the vehicle. (Water dripping from the air conditioning after use is normal.) ● Flat-looking tires or u ...

    Safety Connect
    *: If equipped Safety Connect is a subscription- based telematics service that uses Global Positioning System (GPS) data and embedded cellular technology to provide safety and security features to subscribers. Safety Connect is supported by Toyota's designated response center, which operates 24 hour ...

    No sound is heard from speaker in all modes
    Wiring diagram Inspection procedure 1 Check lcd (liquid crystal display) for lighting Lcd illumination check  turn the ignition switch acc.  Turn the radio receiver assembly on. Standard: lcd illumination of the radio receiver assembly light. 2 Control fader and ...