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:
Using the steering wheel switches
The steering wheel switches can be used to operate a connected cellular phone
or portable digital audio player (portable player).
Operating a Bluetooth® phone using the steering wheel switches
1 Volume
The voice guidance volume cannot be adjusted using these buttons.
2 Off-hook switch
Turns ...
Radio broadcast cannot be received (bad reception)
Inspection procedure
1 Check if radio auto–search functions properly
Check if the radio auto–search functions properly.
Perform the auto–search of the radio and check that it functions
normally.
Standard: the radio auto–search functions properly.
2 Check optional ...
Monitor description
The battery supplies electricity to the ecm even when the ignition switch is
off. This electricity allows the
ecm store data such as dtc history, freeze frame data, fuel trim values, and
other data. If the battery voltage
falls below a minimum level, the ecm will conclude that there is a fault ...