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Signs of a Faulty Transmission Speed Sensor

Signs of a Faulty Transmission Speed Sensor

Transmission Autoplus Auto spare parts Transmission parts
Your car’s transmission speed sensor also known as vehicle speed sensor (VSS) is the one that tells you the speed you are moving with on the road. VSS communicates this information to the engine control unit (ECU). In automatic cars, when the engine control unit receives this information, it selects the right gear to enhance efficient driving depending on your speed.  While it may seem that the sensor is one of the auto parts that can never get damaged, it is actually prone to damage.

Some Reasons that Can Cause the Sensor to Malfunction

  • Corrosion of the transmission speed sensor components
  • Loose wires
  • Cracking within the compartment of the sensor
  • Sensors moving off their shaft completely
  • Lack of efficient connection between the sensor and the ECU
  • Faulty magnetic coil

Here are the signs to watch for when the transmission speed sensor is damaged.

Damaged Cruise Control

When the transmission speed sensor is faulty, it ECU does not receive information about the speed of the car. You may be driving and you feel that the car is not maintaining its speed even when you have not applied the brakes. The ECU reacts by preventing the driver from maintaining velocity when it fails to receive reliable information. You need to have a genuine auto spares parts dealer check examine the ECU and VSS to rule out any other problems.  

Sluggish Shifting

Another common problem when the transmission speed sensor malfunctions is a feeling of longer shifting intervals. You find the car is taking longer to shift gear. The car transmission is dependent on the information it receives from the ECU and if the information is not relayed as it should, the ECU faces difficulties managing the gears. You may assume the problem is minute but there is actually a noticeable waiting period before the car changes gears. It is evident that auto parts repairs are required within the transmission speed sensor and the ECU for the car to perform efficiently.

Problems in Shifting

Difficulties shifting gears occurs for both automatic and manual cars when the sensor malfunctions. For a manual car, the stick may seem harder or rougher or even faster than it normally is. For automatic cars, the car fails to shift the gear when it should such as while climbing a hill. You should have a genuine spare parts mechanic check the sensor as soon as possible. Smooth gear changes are vital to have a safe drive. 

Failing Speedometer

You may notice that your speedometer seems erratic or does not work entirely. The most probable reason is that the dial is not getting reliable speed information and so it becomes unreliable.

Check Engine Light Comes On

When the check engine light comes on, it can be scary and confusing. The light may come on because the ECU realizes it does not get the required speed information and it triggers the light to come on because all these functions are somehow connected to the engine.

Diagnosing the Problem

If any of these problems occur, you need a genuine auto spares parts technician to conduct the right test. Diagnosis is easy because an auto parts technician plugs an electronic tool to your car’s computer and it reads the error code to determine if the sensor is malfunctioning. 


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