Throttle Position Sensor, Idle Switch Description
WARNING: This page is about a different car, the 2002 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.
- The throttle position sensor is a linear-type variable resistor attached to the throttle body. The throttle position sensor contains a plate that has contact points and is located coaxially with the throttle valve.
- This plate rotates together with the throttle valve, and the two contact points slide over the resistor printed on the base plate.
- As the plate rotates, voltage between the VREF terminal and the GND terminal increases in proportion to the rotation. The powertrain control module calculates the voltage ratio between terminals VREF and GND and terminals TVO and GND, and detects the throttle valve opening angle.
- The voltage ratio increases in proportion to the throttle valve opening angle. When the throttle valve is fully closed, the circuit between terminals IDLE and GND is linked by the idle switch, which detects the idle condition.