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:
Inspection procedure
Hand–held tester:
1 Check operation of stop light
Check if the stop lights go on and off normally when the brake pedal is
depressed and released.
2 Inspect stop light switch assy
Check the resistance between the terminals when the
switch is turned on and off.
Standard:
...
Lubrication system
*: The engine oil capacity is a reference quantity to be used when changing the
engine oil. Warm up and turn off the engine, wait more than 5 minutes, and check
the oil level on the dipstick.
■ Engine oil selection
“Toyota Genuine Motor Oil” is used in your Toyota vehicle. Use Toyo ...
Dtc check/clear
1. Dtc check (normal mode)
Notice:
hand–held tester only:
when the diagnostic system is switched from the normal
mode to the check mode, all the dtcs and freeze frame
data recorded in the normal mode will be erased. So before
switching modes, always check the dtcs and freeze frame
data, and ...


