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:
Driving support system
information display
■ Driving support system
information
Select to display the operational
status of the following systems:
LTA (Lane Tracing Assist)
LDA (Lane Departure Alertl)
Dynamic radar cruise control
■ Navigation system-linked
display (if equipped)
Select to display the following
navigation system-linke ...
Emission inspection and maintenance (I/M) programs
Some states have vehicle emission inspection programs which include OBD (On
Board Diagnostics) checks. The OBD system monitors the operation of the emission
control system.
If the malfunction indicator lamp comes on
The OBD system determines that a problem exists somewhere in the emission cont ...
Problem symptoms table
When the malfunction code is not confirmed in the diagnostic trouble code
check and the problem still can
not be confirmed in the basic inspection, proceed to this problem symptoms
tables and troubleshoot according
to the numbered order given below.
*: A/t only ...