Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Ecm power source circuit / Circuit description
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

Other materials:
Heater & air conditioner
Preparation
Sst
Recomended tools
Equipment
Lubricant
...
Wiring
Power source
Location
...
Shifting the shift lever
Vehicles without a smart key system:
While the engine switch is in the “ON” position, depress the brake pedal and
move the shift lever.
Vehicles with a smart key system: While the engine switch is in IGNITION ON mode,
depress the brake pedal and move the shift lever.
When shifting the ...


