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:
Inspection
1. Headlamp dimmer switch assy
Inspect light control switch continuity.
Measure the resistance according to the value(s) in
the table below.
Standard:
Inspect headlight dimmer switch continuity.
Measure the resistance according to the value(s) in
the tabl ...
If your vehicle overheats
The following may indicate
that your vehicle is overheating.
The engine coolant temperature
gauge is in the red zone or a loss
of engine power is experienced.
(For example, the
vehicle speed does not
increase.)
"Engine Coolant Temp High
Stop in a Safe Place See
Owner's Manual" is shown
on ...
Replacement
1. Work for preventing gasoline from spilling out
2. Remove cylinder head cover no.2
Remove the 2 nuts, 2 clips and cylinder head cover.
3. Disconnect ventilation hose
Disconnect the ventilation hose from the cylinder head
cover.
4. Disconnect engine wire
Disconnect ...


