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:
Body dimension drawings
Engine compartment
Body opening areas (side view: front)
Body opening areas (side view: rear)
Sedan
Body opening areas (rear view)
Sedan
Under body
Under body
Front suspension crossmember
Front suspension crossmember
...
Bluetooth® Audio
Operating a Bluetooth® enabled portable player
1 Power
2 Volume
3 Select an album, fast-forward or reverse
4 Repeat play
5 Random playback
6 Selecting an item
7 Displays text message
8 Playback
9 Playback/pause
10 Search playback
11 Select a track
Selecting an album
Press (
) or ...
How to proceed with troubleshooting
1 Vehicle brought in
2 Customer problem analysis check and symptom check
3 Problem symptoms table
Without applicable symptoms, proceed to ”a”
with applicable symptoms, proceed to ”b”
4 Perform troubleshooting in the following method, depending on
malfunction symptom ...


