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 procedure
Hint:
perform the troubleshooting of dtc p0335 first. If no trouble is
found, troubleshoot the engine mechanical
systems.
Read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records
the engine conditions when a malfunction is detected. When tr ...
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 ...
Cleaning and protecting the vehicle exterior
Perform the following to protect the vehicle and maintain it in prime condition:
● Working from top to bottom, liberally apply water to the vehicle body, wheel
wells and underside of the vehicle to remove any dirt and dust.
● Wash the vehicle body using a sponge or soft cloth, such a ...


