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:
Stopping
► Automatic transmission or continuously
variable transmission
1 With the shift lever in D, depress the brake pedal.
2 If necessary, set the parking brake.
If the vehicle is to be stopped for an extended period of time, shift the shift
lever to P or N. (, 174, 176) ► Manual ...
Towing your vehicle with 4 wheels on the ground
To prevent damage to your vehicle, perform the following procedures before towing.
1 Shift the shift lever to N.
2 Turn the engine switch to the “ACC” position (without a smart key system) or
ACCESSORY mode (with a smart key system).
(, 166) Ensure that the audio system and other powered de ...
On–vehicle inspection
1. Inspect turn signal flasher relay circuit
Disconnect the connector from the turn signal flasher
relay and inspect the connector on wire harness side as
shown in the chart.
Standard:
Connect the connector to the turn signal flasher and inspect
the wire harness side connector ...


