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:
Circuit description
The shift solenoid valve sl is turned ”on” and ”off” by signals from the ecm
in order to control the hydraulic
pressure operation, the lock–up relay valve, which then the controls operation
of the lock–up clutch.
Fail safe function:
if the ecm detects a malfunction, it turns the ...
Brake Hold
The brake hold system
keeps the brake applied
when the shift lever is in D,
B (vehicles without paddle
shift switches), M (vehicles
with paddle shift switches)
or N with the system on and
the brake pedal has been
depressed to stop the vehicle.
The system releases the
brake when the accelerator
peda ...
Air conditioning filter
The air conditioning filter must be changed regularly to maintain air conditioning
efficiency.
Removal method
1Turn the engine switch off.
2 Open the glove box. Slide off the damper.
3 Push in the glove box on the vehicle’s outer side to disconnect the claws.
Then pull out the glove box ...


