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:
On–vehicle inspection
1. Inspect w/receiver condenser assy
if a fin of the w/receiver condenser assy is dirty, clean it with
water and dry it with compressor air.
Notice:
do not damage the fin of the w/receiver condenser assy.
if a fin of the w/receiver condenser assy is bent, make it
straig ...
Inspection procedure
1 Check fuse(ecu–ig)
Remove the ecu–ig fuse from the instrument panel j/b.
check the continuity of the ecu–ig fuse.
Ok: continuity
2 Inspect terminal voltage(b)
Remove the cruise control ecu assy with connector still
connected.
turn the ignition switch ...
Alarm
The alarm uses light and
sound to give an alert when
an intrusion is detected.
The alarm is triggered in the
following situations when
the alarm is set:
A locked door or trunk is
unlocked or opened in any
way other than using the
entry function (if equipped),
wireless remote control,
mechani ...