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
Hint:
if dtc p0441 (purge flow), p0446 (vsv for ccv or vsv for pressure
switching valve), p0451, p0452
or p0453 is output with dtc p0442 or p0456 , first troubleshoot
dtc p0441, p0446, p0451, p0452 or p0453. If no malfunction is detected,
troubleshoot dtc
p0442 or p0456 next.
...
On–vehicle inspection
1. Inspect turn signal flasher relay circuit
Disconnect the connector from the turn signal flasher
relay and inspect the connector on wire harness side as
shown in the chart.
Standard:
Connect the connector to the turn signal flasher and inspect
the wire harness side connector ...
Adjustment
Hint:
in the rh side, work in the same procedure as in the lh side.
Since the centering bolt is used as a door side hinge bolt,
the door hinge cannot be adjusted with it on. Substitute
the bolt with washer for the centering bolt.
1. Inspect rear door panel sub–assy lh
Check ...