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:
How to proceed with troubleshooting
Hint:
troubleshooting of the wireless door lock control system is based on
the premise that the power door
lock system is operating normally. Therefore, before troubleshooting the
wireless door lock control system,
first make certain that the the power door lock system is operating
...
Circuit description
The airbag front rh sensor circuit consists of the airbag sensor assy center
and airbag front rh sensor.
Dtc b1156/b1157/15 is recorded when a malfunction is detected in the airbag
front rh sensor circuit.
Wiring diagram
...
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 ...


