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:
Precaution
1. Handling precautions on steering system
care must be taken when replacing parts. Incorrect replacement may
affect the performance of the
steering system and result in a driving hazard.
2. Handling precautions on srs airbag system
the vehicle is equipped with srs (suppl ...
How to proceed with troubleshooting
1 Vehicle brought to workshop
2 Customer problem analysis
3 Problem symptom confirmation
4 Circuit inspection
5 Repair or replace
6 Confirmation test
7 End
Customer problem analysis check
...
What to do if... (Troubleshooting)
If you have a problem, check the following before contacting your Toyota dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
● If you lose your keys or mechanical keys, new genuine keys or mechanical keys
can be made by your Toyota dealer.
● If you lo ...


