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:
Cigarette lighter assy
Replacement
Hint: components:
1. Remove floor shift shift lever knob sub–assy (m/t transaxle)
2. Remove console panel upper
3. Remove cigarette lighter cover
Disengage the 2 claws and remove the cigarette lighter
cover.
4. Remove cigarette lighter assy
Turn the socket in ...
Circuit description
When the ignition switch is turned on, battery positive voltage is applied to
the coilwhich closes the contacts
of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.
This signal causes current to flow to the coil, closing the contacts of the efi
relay and supplyin ...
Replacement
Hint: components:
1. Precaution
2. Disconnect battery negative terminal
3. Remove horn button assy
Place the front wheels facing straight ahead.
using a torx socket wrench (t30), loosen the 2 torx
screws until the groove along the screw circumference
catches on the screw ca ...


