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:

    Horn
    To sound the horn, press on or close to the mark. CAUTION ■Caution while driving Do not adjust the steering wheel while driving. Doing so may cause the driver to mishandle the vehicle and cause an accident, resulting in death or serious injury. ■After adjusting the steering wh ...

    Removal & installation and disassembly & reassembly
    1. Remove oxygen sensor Remove a clip and tear off the floor mat.  disconnect a oxygen sensor connector. Remove the oxygen sensor. 2. Remove tail pipe assy Remove 2 bolts, 2 springs and tail pipe assy. 3. Remove floor panel brace front Remove 2 nuts and the ...

    Circuit description
    The p/t squib (lh) circuit consists of the airbag sensor assy center and seat belt pretensioner (lh). It causes the srs to deploy when the srs deployment conditions are satisfied. Dtc b0135/73 is recorded when a short is detected in the p/t squib (lh) circuit. Wiring diagram ...