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:
Glossary of sae and toyota terms
This glossary lists all sae–j1930 terms and abbreviations used in this manual
in compliance with sae recommendations,
as well as their toyota equivalents.
...
Inspection procedure
1 Check connector
Disconnect the negative (–) terminal cable from the battery, and wait at
least for 90 seconds.
check the connection of the combination meter connector and the
airbag sensor assy center connectors.
Ok:
the connectors are connected.
2 Check combination ...
Circuit description
1 Check p squib circuit(airbag sensor assy center – instrument
panel passenger airbag assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the instrument panel ...