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:
Changing the engine switch positions
1 “LOCK”
The steering wheel is locked and the key can be removed. (Vehicles with an automatic
transmission or continuously variable transmission: The key can be removed only
when the shift lever is in P.) 2 “ACC”
Some electrical components such as the audio system can be used.
3 “ON ...
Sound quality is bad only when playing tape
Inspection procedure
1 Replace cassette tape with another and recheck
Replace the cassette tape with another and recheck.
Replace the faulty cassette tape with the normal one to see if the
same trouble occurs again.
Standard: malfunction disappear.
2 Check for any foreig ...
Outside vehicle
General maintenance
Performing these maintenance checks on the vehicle in the owner’s
responsibility. The owner may
perform the maintenance or take the vehicle to a service center.
Check the parts of the vehicle described below on a daily basis. In most cases,
special tool are not
requir ...


