If you’re thinking about buying a truck, you should know that the transmission speed sensor is a crucial part of the control and monitoring system. Although it’s a small and often overlooked part, it plays a critical role in the proper functioning of your car.
When it fails, it can cause a range of issues, from performance problems to costly transmission damage. Here, we show you in detail how to tell if your speed sensor is failing by identifying the most common signs.
What is the transmission speed sensor?
Before we dive into the signs of a faulty sensor, it’s important to understand what it is and what its function is. The transmission speed sensor, also known as a VSS (Vehicle Speed Sensor), is a part located in or near the transmission.
Its main task is to measure the speed at which the transmission shaft is turning and send this information to the engine control computer (ECU). The ECU uses the sensor signal to perform a number of essential functions, such as automatic gear shifting, speed control and management of the anti-lock braking system (ABS).
It is also crucial for the proper operation of cruise control and other driver assistance systems.
Why is the transmission speed sensor important?
The transmission speed sensor is an essential part of a vehicle’s control and monitoring system, and its importance lies in its critical role in the operation and safety of the car. Here are some of the key reasons why it is so important:
- Transmission control
The speed sensor plays a key role in automatic transmission control. It provides accurate vehicle speed information, allowing the transmission control unit to make informed decisions about when to change gear.
- Safety
Correct operation of the speed sensor is essential for the proper performance of the anti-lock braking system (ABS) and traction control systems. These systems depend on accurate tyre speed information to operate properly and enhance vehicle safety.
If the sensor fails, these systems may not operate effectively, which could jeopardise the safety of the driver and passengers.
- Cruise control
Many modern vehicles are equipped with cruise control systems that allow drivers to maintain a constant speed on the road. These systems use sensor information to adjust vehicle speed according to the driver’s preferences.
If not working properly, cruise control can be ineffective or even dangerous if it cannot maintain a fixed speed.
- Diagnosing problems
The speed sensor also plays a crucial role in diagnosing vehicle problems. When it fails, it often activates the check engine light, alerting the driver to a potential problem.
This allows technicians to identify and fix problems before they become more serious and costly.
- Driver experience
A well-maintained transmission speed sensor contributes to a smoother and more comfortable driving experience. It prevents abrupt gear changes and allows control systems to function optimally, resulting in a safer and more enjoyable drive.
6 signs of a faulty speed sensor
Identifying a faulty transmission speed sensor can be a challenge, as the signs can vary depending on the type of truck and transmission system. However, here is a list of the most common signs that can indicate a problem with this sensor:
- Check engine light on
One of the most common indicators of a speed sensor problem is the activation of the check engine light on the dashboard. When the ECU detects an irregular signal from the VSS, it will turn on this warning light to alert you to a possible problem.
- Shifting problems
If you notice that your truck is having difficulty shifting or is shifting abruptly and irregularly, this could be due to a fault in the transmission speed sensor. The VSS plays a key role in automatic transmission control and can affect the timing of gear changes.
- Speedometer inactive
Another sign of a transmission speed sensor problem is a speedometer that is not working properly. If it does not show an accurate speed or stays at zero even when you are moving, the sensor is probably not in good condition.
- Loss of power
A faulty VSS can also cause a loss of power to your truck. This is because the ECU uses speed information to adjust engine power. If the sensor provides incorrect data, the engine may not run efficiently.
- ABS brakes activating incorrectly
The anti-lock braking system (ABS) relies on the activity information provided by the sensor. If you notice them activating incorrectly or in situations where they shouldn’t, this could be a sign of a problem with the speed sensor.
- Cruise control problems
If your vehicle is equipped with cruise control and you notice that it does not consistently maintain the selected speed, the sensor could be to blame. Cruise control uses speed data to maintain a constant road speed.
So far we have seen 6 signs of a faulty speed sensor. Early identification and correction of a problem with this part of your vehicle can help prevent more serious and costly problems in the future. Remember, keeping it in good condition is essential to keep your truck running safely and efficiently, and we hope you found this article helpful!