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:
Customizing vehicle features
It is possible to customize the language and Eco Driving Indicator Light settings
using the “DISP” switch.
When customizing vehicle features, ensure that the vehicle is parked in a safe
place with the shift the shift lever to P (continuously variable transmission) or
N (manual transmissio ...
On–vehicle inspection
1. Inspect pressure switch no.1.
Magnetic clutch control:
inspect pressure switch operation.
Set on the manifold gauge set.
Connect the positive (+) lead from the ohmmeter to
terminal 4 and the negative (–) lead to terminal 1.
Check continuity between termin ...
Inspection
1. Inspect defogger relay (marking: def)
Remove the defogger relay from the instrument panel
j/b.
inspect the defogger relay.
Standard:
If the result is not as specified, replace the relay ...