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:
Outside temperature display
The temperature display shows temperatures within the range of -40°F (-40°C)
to 122°F (50°C).
► Type A
► Type B
► Type C
► Type D
■The outside temperature is displayed when
►Vehicles without a smart key system
The engine switch is in the “ON ...
Circuit description
The park/neutral position switch detects the shift lever position and sends
signals to the ecm.
Monitor description
The park/neutral position switch detects the gearshift position and sends a
signal to the ecm.
For security, the park/neutral position switch detects the gearshift positio ...
Customizing vehicle features
It is possible to customize the language and Eco Driving Indicator Light settings
using the “DISP” switch.
When customizing vehicle features, ensure that the vehicle is parked in a safe
place with the shift the shift lever to P (continuously variable transmission) or
N (manual transmissio ...


