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:
Drive shaft / propeller shaft
Preparation
Sst
Recomended tools
Equipment
Lubricant
...
Basic inspection
Resistance measuring condition of electronic parts
unless stated, all resistance is measured at an ambient
temperature of 20 c (68 °F). As the resistance
may be outside the specifications if measured at high temperatures
immediately after
the vehicle has been running, measu ...
Inspection procedure
1 Check p/t squib(lh) circuit(airbag sensor assy center – front seat
outer belt assy lh)
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 seat belt pretensio ...