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

Wiring diagram

Inspection procedure

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    Trip information
    ■ Switching the display Items displayed can be switched by pressing the “DISP” switch. ■ Odometer Displays the total distance the vehicle has been driven. Except vehicles with a manual transmission: Press and hold the “DISP” switch to change the display to the Eco Driving ...

    On–vehicle inspection
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    Checking the engine coolant
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