5 Functions of the Throttle Position Sensor – The throttle position sensor or TPS sensor is a car component that is connected to the gas valve (throttle gas). The function of the TPS sensor is to regulate and balance fuel and emissions in the car engine.
5 Functions of the Throttle Position Sensor
This component is attached to the throttle body and is always connected to the throttle valve (gas valve). However, what exactly is the function of this TPS sensor? How does it work on a car?
To understand better, I will discuss the function and how the TPS sensor works on cars.
Its main function is to detect changes in the gas throttle. This sensor is responsible for ensuring the gas throttle remains in the appropriate position and opening angle.
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If there is a shift, the sensor will send an electrical signal that is sent to the ECU (Electronic Care Unit). After the signal is processed, injection or fuel supply will then be carried out into the combustion chamber.
In addition, other functions of the TPS sensor are;
- Becomes engine mode when the gas throttle position is closed (usually when the car is idle), half-opened, and fully open.
- Becomes emission control, especially when the gas throttle is in the fully open position and when the air conditioner is off.
- Controls the fuel to stop when the engine decelerates (decelerates).
- In charge of correcting the ratio of the amount of air and fuel.
- In charge of correcting whether there is an increase in power in the engine.
Types of TPS Sensors
In most car engines currently available, there are three types of TPS sensors that are often used. that is;
- Variable resistor type
- Point contact type
- Combination type (integrates variable resistors and contact points).
How the TPS Sensor Works
After discussing the function of the TPS sensor and its types, let’s move on to the next discussion about how the TPS sensor works.
As previously mentioned, the function of the TPS sensor is to detect changes in the position and angle of the gas throttle opening. How can the TPS sensor detect this? First, it helps us to know in advance the components of the TPS sensor.
1. TPS Sensor Composition Components
TPS sensors are generally designed with three wires (some cars have TPS sensors with four wires). These three wires are connected to the potentiometer.
On the TPS sensor, the potentiometer functions to measure the position and angle of the gas throttle opening.
When working, the potentiometer acts like a resistor whose pressure is always changing. Therefore, the TPS sensor requires three auxiliary cables.
The first wire on the TPS sensor is for the reference voltage, the second wire is for the reverse voltage, and the third wire is for resistance.
2. How does the TPS Sensor work?
When you start the car, the ECU will send an output voltage or a reference voltage of 5v which is then received by the VREF analog sensor. From the analog sensor, the voltage returns to the ECU via the TP Signal.
When the car is idle or disabled, the voltage coming out of the sensor is below 0.7 Volts. While in full load conditions, the output voltage can reach 4.5 Volts.
The potentiometer can vary in pressure. Therefore, the output voltage or output generated by the TPS sensor is always changing.
The potentiometer can be shifted from the lowest voltage (point P1) to the highest voltage (point P6). Everything depends on the pressure received by the gas pedal, especially if you drive a manual car.
From this, it can be seen that the functions of the TPS sensor are numerous. Its existence is also very vital, namely so that the combustion process in the engine remains optimal.