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:
Optimal use of the multimedia system
On the “Sound Settings” screen, sound quality (Treble/Mid/ Bass), volume balance
can be adjusted.
How to adjust the sound settings and sound quality
1 2 3 Select “-” or “+” to adjust the treble, mid or bass to a level between
-5 and 5.
4 5 Select “Front” or “Rear” to adjus ...
Inspection procedure
1 Check seat position air bag sensor
Sst 09843–18040
Turn the ignition switch to on, and wait at least for 20 seconds.
clear the dtc stored in memory .
turn the ignition switch to lock, and wait at least for 20
seconds.
turn the ignition switch to on, and wait at ...
Mass or volume air flow circuit
Dtc p0100 mass or volume air flow circuit
Dtc p0102 mass or volume air flow circuit
low input
Dtc p0103 mass or volume air flow circuit
high input
Circuit description
The maf (mass air flow) sensor measures the amount of air flowing through the
throttle valve. The ecm
uses this information ...


