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:
Replacement
Hint: components:
1. Precaution
2. Disconnect battery negative terminal
3. Remove instrument panel sub–assy lower
Remove the screw from the glove compartment door
stopper sub–assy.
pull the instrument panel sub–assy lower to remove it.
4. Separate passenger airbag co ...
Inspection procedure
Hint:
when the throttle position is slightly opened (the accelerator pedal
is slightly depressed) because a
floor carpet is overlapped on the accelerator pedal, or if not fully
releasing the accelerator pedal, etc.,
Dtc p505 will possibly be detected.
Read freeze frame data using the ...
Supplemental restraint system
Preparation
Sst
Recomended tools
Equipment
...


