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:
Replacement
1. Work for preventing gasoline from spilling out
2. Remove front wheels
3. Remove engine under cover rh
4. Remove engine under cover lh
5. Drain coolant
6. Remove cylinder head cover no.2
Remove the 2 nuts, 2 clips and cylinder head cover.
7. Disconnect radiator hose inlet
&nb ...
Fuel
Preparation
Sst
Recomended tools
Ssm
Equipment
...
Inspection procedure
Hint
Advanced timing over
(valve timing is out of specified range)
P0011
Retarded timing over
(valve timing is out of specified range)
P0012
If dtc p0011 or p0012 is displayed, check the vvt system circuit.
Read freeze frame data using the hand–held tester o ...


