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:
Removal & installation and disassembly & reassembly
1. Remove bench type rear seat cushion assy
2. Remove rear floor service hole cover
Remove the rear service hole cover.
Disconnect the fuel pump and vapor pressure sensor
connector.
3. Work for preventing gasoline from spilling out
Start the engine.
after the engi ...
Glossary of sae and toyota terms
This glossary lists all sae–j1930 terms and abbreviations used in this manual
in compliance with sae recommendations,
as well as their toyota equivalents.
...
How to proceed with troubleshooting
The hand–held tester can be used at step 3, 4, 5, 7, 10.
1 Vehicle brought to workshop
2 Customer problem analysis
3 Connect hand–held tester to dlc3
Hint:
if the display indicates a communication fault in the tool, inspect dlc3.
4 Check dtc and freeze frame data
Hint:
record or pr ...


