Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Fuel pump control circuit / Circuit description
Toyota Corolla (E120): Circuit description
In the diagram below, when the engine is cranked, current flows from terminal st2 of the ignition switch to the starter relay coil and also current flows to terminal sta of the ecm (sta signal).
When the sta signal and ne signal are input to the ecm, tr is turned on, current flows to the coil of the circuit opening relay, the relay switches on, power is supplied to the fuel pump and the fuel pump operates.
While the ne signal is generated (engine running), the ecm keeps tr on (circuit opening relay on) and the fuel pump also keeps operating.
Wiring diagram
Other materials:
Diagnosis system
Description
when troubleshooting obd ii vehicles, the only difference
from the usual troubleshooting procedure
is that you need to connect an obd ii scan tool complying
with sae j1987 or a hand–held tester to the
vehicle, and read off various data output from the
vehicle†...
Inspection procedure
1 Check d squib circuit(airbag sensor assy center – horn button
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 horn button assy.
for the oran ...
If a warning message or indicator is displayed (vehicles with a multi-information
display)
If a warning is shown on the multi-information display, stay calm and perform
the following actions:
1 Master warning light
The master warning light also comes on or flashes in order to indicate that a message
is currently being displayed on the multiinformation display.
2 Multi-information d ...