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Input Signals

  1. Engine coolant temp. signal circuit

    The engine coolant temp. sensor detects the engine coolant temperature and has a built-in thermistor that's resistance varies according to the engine coolant temperature. The engine coolant temperature is then sent to TERMINAL THW of the engine control module as a control signal.

  2. Intake air temp. signal circuit

    The intake air temp. sensor is installed in the mass air flow meter and detects the intake air temperature which is input as a control signal to TERMINAL THA of the engine control module.

  3. Oxygen density signal circuit

    The oxygen density in the exhaust emissions is detected by the heated oxygen sensor and sent as a control signal to TERMINAL OX1B of the engine control module.

  4. RPM signal circuit

    The camshaft and crankshaft positions are detected by the camshaft position sensor and crankshaft position sensor. The camshaft position is sent as a control signal to TERMINAL G2+ of the engine control module, and engine RPM is sent into TERMINAL NE+.

  5. Throttle position signal circuit

    The throttle body assembly detects the throttle valve opening angle and sends it as a control signal to TERMINALS VTA1 and VTA2 of the engine control module.

  6. Vehicle speed circuit

    The speed sensors detect the vehicle speed and send it to the skid control ECU with actuator, which sends it to TERMINAL SPD of the engine control module via the combination meter.

  7. Battery signal circuit

    Voltage is constantly applied to TERMINAL BATT of the engine control module. When the ignition SW is turned on, the voltage for the engine control module start-up power supply is applied to TERMINALS +B and +B2 of the engine control module via the EFI relay.

  8. Stop lamp SW signal circuit

    The stop lamp SW is used to detect whether the vehicle is braking or not and the signal is sent to TERMINAL STP of the engine control module as a control signal.

  9. Starter signal circuit

    To confirm whether the engine is cranking, the voltage that is being applied to the starter motor during cranking is detected and the signal is sent to TERMINAL STA of the engine control module as a control signal.

  10. Engine knock signal circuit

    Engine knocking is detected by the knock control sensor and the signal is sent to TERMINAL KNK1 as a control signal.

  11. Air fuel ratio signal system

    The air fuel ratio is detected and sent as a control signal to TERMINAL A1A+ of the engine control module.