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

    Share this page:

    Other materials:

    Overhaul
    Hint: components: 1. Remove front wheel 2. Disconnect front stabilizer link assy lh Remove the nut and disconnect the front stabilizer link assy lh from the shock absorber assy front lh. Hint: if the ball joint turns together with the nut, use a hexagon (6 mm) wrench to hold the st ...

    Source voltage drop
    The srs is equipped with a voltage–increase circuit (dc–dc converter) in the airbag sensor assy center in case the source voltage drops. When the battery voltage drops, the voltage–increase circuit (dc–dc converter) functions to increase the voltage of the srs to normal voltage. ...

    Shifting the shift lever
    Vehicles without a smart key system: While the engine switch is in the “ON” position, depress the brake pedal and move the shift lever. Vehicles with a smart key system: While the engine switch is in IGNITION ON mode, depress the brake pedal and move the shift lever. When shifting the ...