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:
Overhaul
1. Remove control shift lever bush
Remove the control shift lever bush from the selecting
bellcrank assy.
2. Remove selecting bellcrank dust cover no.1
Remove the selecting bellcrank dust cover no.1 From the
selecting bellcrank assy.
3. Remove selecting bell crank no.2
...
Engine mechanical
Preparation
Sst
Recomended tools
Ssm
Equipment
Exhaust
Preparation
Equipment
...
Inspection
1. Cooling fan relay
Inspect the cooling fan relay continuity.
Using an ohmmeter, check that there is continuity
between terminals 1 and 2.
If there is no continuity, replace the relay.
Check that there is no continuity between terminals
3 and 5.
If there is conti ...


