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:
Data list/active test
1. Data list
Hint:
according to the data list displayed by the obd ii scan tool or hand–held
tester, you can read the value
of the switch, sensor, actuator and so on without parts removal. Reading the
data list as the first step of
troubleshooting is one method to shorten labor time.
W ...
Replacement
Hint: components:
1. Table of bolt, screw and nut
Notice:
be sure to tape the tip of the screwdriver when using it to disengage the
meshing of the clips and
claws.
Hint:
indicate the bolts, screws and nuts, which are necessary for installation and
removal of the instrument panel,
in th ...
Inspection
1. Headlamp dimmer switch assy
Inspect light control switch continuity.
Measure the resistance according to the value(s) in
the table below.
Standard:
Inspect headlight dimmer switch continuity.
Measure the resistance according to the value(s) in
the tabl ...


