Symptoms of a Bad Transmission Speed Sensor

Symptoms of a Bad Transmission Speed Sensor

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Electronics in today’s cars and trucks are extremely complex. The speedometer provides on-time driving information concerning our vehicle’s level of speed. The speedometer is controlled by the speedometer on the dashboard, the cable attached from the speedometer to the driving shaft, and the speedometer sensors attached to the driveshaft for measuring speed. Here are some of the Transmission Speed Sensor Symptoms that we’re going to get into in this article:

  • Speedometer Doesn’t Work
  • Cruise Control Doesn’t Work
  • Engine Light Comes On
  • Car Won’t Start Properly
  • Vehicle Loses Power
  • Gear Shifting Become Harsh & Improper

The speed sensor is located in your vehicle’s transmission and is designed to record the driveshaft’s speed, which often rotates. The sensor sends the information it detects via the cable of the speedometer and your car’s built-in computer. This process helps to convert the electrical pulses into a digital speed. 

Symptoms of a Faulty Transmission Speed Sensor

Ultimately, the figure shown on your speedometer communicates the level of speed of your vehicle. But when your speed sensor is faulty, the readings of your speedometer will become incorrect. This problem can be very dangerous as it can lead to road accidents. Below are the symptoms of a faulty speed sensor in the vehicle:

1. Speedometer does not work

You may be wondering why your digital speedometer or a manual speedometer stop working? This is a sure sign of a faulty speed sensor. Also, inaccurate readings from the speedometer is a direct symptom that you need to visit the mechanic for a repair. 

Suppose you have observed that you are driving faster or slower than what the speedometer indicates. In that case, it is advisable to have your vehicle inspected by your mechanic, as this could be a problem with the serviceable sensor or an indication that the speed sensor needs replacement. 

If you have observed any of the above issues in your vehicle, it will not harm repair or fix such damages to prevent future accidents and troubles. Quick fixing of your speed sensor can improve safety, not only for you but for others on the road. 

2. Cruise control fails to work

Most car owners fail to realize that the speed sensor is a vital body part of the vehicle’s cruise control system. If the sensor is faulty, it will therefore fail to send a signal to the CPU. This directly forestalls the vehicle’s ability to adjust speed to your anticipated speed. 

One measure of safety from car producers to users against accidents is designing the cruise control and the speed sensor. Once your speed sensor is faulty, it will be difficult to engage your vehicle’s cruise control. Recent vehicles from producers show faulty cruise control on the dashboard of your vehicle. This light that illuminates on the dashboard may not need any special activation to come on. Once you are experiencing a cruise control problem, know that your speedometer sensor is faulty.

3. Check Engine light comes on

As stated earlier, the speed sensor’s location is found in the transmission system and attached to the driveshaft. This permits the Check Engine Light to come up on the dashboard when there is any sensor issue in your vehicle. 

You may be surprised about the light beeping in your vehicle. It is wise to take it seriously because this sign is a good thing, and it should not be avoided. You are advised to see the mechanic for a checkup or a proper diagnosis of the problem.

4. Vehicle loses power

Presently, small vehicles and trucks are made with electronic fuel injectors. The on-board computer coordinates this injector. The EFI allocates fuel to the engine from its multiple sensors. Specifically, the speed sensor. 

Suppose there is an observation that the vehicle is losing balance when you apply pressure to the throttle. This is one direct sign of a faulty speed sensor in your vehicle. This problem should not be taken lightly, as it can result in other mechanical issues within your vehicle. It is advised to take your vehicle to a certified mechanic to repair or properly diagnose the problem. 

5. Gear shifting becomes harsh or improper

One other symptom you notice if your vehicle’s transmission speed sensor is getting worse is the harsh gear shifting. This is due to the incapacity experienced by the powertrain control module (PCM). The PCM is typically designed to regulate the shifting of gears. 

But it will not be able to correctly carry out this function with the transmission due to the lack of a valid speed signal coming from the engine speed sensor. What happens as a consequence is the rough, harsh, and improper shifting of the transmission. It is either the transmission shifts faster than it should or the shifting is hard and harsh. 

6. Car will not start

You will also notice that your car won’t start if the transmission speed sensor is failing. It may also be that the vehicle will find it difficult to start. The engine management control completely loses power if the Transmission speed sensor does not work. While the engine may give some cranking sounds, it will not start, not thanks to the lack of triggers. When this happens, the thing to do is to hire a professional and seasoned technician to look at the car and diagnose possible causes.

Why Does the Speed Sensor Fail?

Like almost all electronic components of a car, the sensor suffers primarily from oxidation of contacts and violation of wiring integrity. Often, the problem can be identified during a visual inspection, although it is worth using a tester for accuracy. 

Each of the contacts must be disconnected and checked. Oxidized and simply dirty contacts must be cleaned and coated with special grease. Another weak point of the most common systems for determining a car’s speed is the speedometer cable.

Over time, it breaks down in several places at once, which ultimately affects the vehicle speed’s correct determination. The old cable must be changed, and before installation, just in case, cover with machine oil.

Oddly enough, the most common and seemingly reliable speed detection systems do not tolerate driving with sharp increases in speed. Because of this, the integrity of the plastic tail in the sensor is quickly broken. 

The cable also begins to flake and crack. As mentioned above, the cable must be lubricated. The tightness of the plastic tail’s attachment must be controlled – it must be high, which will prevent subsequent loosening of the attachment socket.

Why a Transmission Speed Sensor?

When you look directly into the dashboard of your vehicle and any part of it you observe that takes the current kilometer per hour (or miles per hour) is what is called the transmission speed sensor. It is also called the engine speed sensor. 

The function of the engine sensor does not stop there. It receives and determines all speed information and recording before it sends it to the engine control department. The purpose of sending the information is to ensure that the control compartment regulates the entire vehicle system, including air-to-fuel ratio, ignition timing, combustion chamber, and transmission shift points.  

Typically, the transmission is naturally designed to shift smoothly, automatically, and hydraulically controlled, but the timing of the shifting can be extended due to a faulty transmission speed sensor. What you notice is the extended interval as transmission shifts. 

Typically, automatic transmission means that drivers do not need to be mechanically shifting or changing their vehicle’s gears at intervals because the process is being carried out for them by the automatic transmission. The implication of this is that the shifting process makes things easier than when drivers have to change gears manually. 

In the end, the internal components of the engine, including mechanical gears, hydraulic lines, and valve frames. When you observe that your transmission is shifting roughly, the best thing to do is call on a technician to carry out a diagnosis.

Transmission Speed Sensor: Key Features

  • Works when needed wheel speed rotates
  • Resistant to and suitable for harsh environmental conditions
  • The automatic design makes operation easier and
  • The magnetic operation makes the sensor reliable and durable
  • Seamless flushing and mounting options

Functions of the Transmission Speed Sensor

As noted above, the engine speed sensor carries out the primary function of determining the current miles per hour. Besides, it is also responsible for other tasks in the vehicle. They include:  

  • It detects target wheel gear 
  • Produces a digital signal relative to the rotation of the wheel speed
  • Can be used to perform diagnosis and as shift points 

How an Engine Speed Sensor Works

As the name suggests, the transmission speed sensor is closely linked with your car’s engine transmission. The connection between the transmission and the speed sensor makes the sensor detect the ratio of the car gear. While classic vehicles come with a single transmission speed sensor, the new models are designed with two sensors. 

One of the sensors —called input shaft speed — is responsible for keeping a record of the transmission input shaft speed. The other —referred to as the output shaft speed sensor —takes track of the transmission’s output shaft speed. They both function together to send information to the engine control unit. The input shaft is linked with the control unit by the vehicle’s clutch. This is to allow the shaft to work at the same speed.

On the other hand, the output shaft speed sensor connects to the drive wheels, allowing for an increase or reduction in speed in line with the level of gear you pick. This is to ensure that the wheels move almost at a relatively manageable speed with the speed of the engine. The essence of controlling the speed of the wheel is to allow for enhanced speed and efficient performance. However, it is difficult to achieve these results without the transmission speed sensor.

The output shaft speed sensor is designed to identify the wheels of the drive wheel before returning the information to the control unit inside the engine. The control unit processes the information it receives before automatically selecting the needed gear that will sustain the smooth and safe experience on the wheel.

Frequently Asked Questions

Q: Where is the location of the Speed Sensors?

The speed sensor in your vehicle is found close to the transmission’s output shaft in your vehicle’s engine. The placement of the speed sensor is strategically placed to detect the rotation of the driveshaft. 

Q: Can I clean the speed sensor of my vehicle?

Yes, you can and need to get rid of any dirt accumulated by your transmission speed sensor. The fact is that the speed sensor of a vehicle will gather dirt and dust from the anti-lock brake system and other vehicle regions. Regular cleaning also prevents the quick damaging of your anti-lock brake system. do not wait for an extended period before you clean your speed sensor. The longer you wait, the more room you give for the component to rust and corrode. 

Q: Can I drive my vehicle with a bad speed sensor?

Yes, you can, but it is not advisable to drive a vehicle with a faulty speed sensor. This is to avoid further complications of the mechanical components and also accidental occurrence from taking place. Visit the nearest mechanic for a repair or proper diagnosis of the problem of the vehicle.

Final Thoughts

Now you have the necessary information you need at your fingertips. Symptoms of failing transmission speed sensors are clear and it only takes a careful driver or car owner to quickly notice this when things go wrong. You shouldn’t be caught unawares or have your vehicle go from bad to worse conditions before you notice some of these signs from a bad transmission speed sensor.

Here is the truth: you may not successfully solve the issue of a failing transmission problem. What you need to do is to hire the service of a technician. If you observe any of the symptoms highlighted above, it will not harm to swiftly call a certified mechanic for a repair or replacement of your speed sensor. 

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