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:
Inspection procedure
1 Check harness and connector(transmission control switch –
body ground)
Disconnect the transmission control switch connector of
shift lever assy.
measure the resistance according to the value(s) in the
table below.
Standard:
2 Inspect transmission control switch
M ...
Basic inspection
Resistance measuring condition of electronic parts
unless stated, all resistance is measured at an ambient
temperature of 20 c (68 °F). As the resistance
may be outside the specifications if measured at high temperatures
immediately after
the vehicle has been running, measu ...
Inspection procedure
1 Inspect skid control ecu connector(+bs terminal voltage)
Disconnect the skid control ecu connector.
measure the voltage between terminals +bs (2) and gnd
(1, 23) of skid control ecu harness side connector.
Voltage: 10 – 14 v
2 Reconfirm dtc
Check the dtc .
Ok :
...


