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:
If the engine will not start
If the engine will not start even though correct starting procedures are being
followed , consider each of the following points:
The engine will not start even though the starter motor operates normally.
One of the following may be the cause of the problem:
● There may not be sufficient f ...
Overhaul
1. Remove oil pump relief valve
Remove the oil pump relief valve plug, oil pump relief
valve spring and oil pump relief valve.
Oil pump relief valve plug
oil pump relief valve spring
oil pump relief valve
2. Inspect oil pump assy
Remove 3 screws and o ...
Inspection procedure
1 Check side squib(lh) circuit(airbag sensor assy center – front
seat airbag assy lh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the front seat airbag assy ...


