Why Speedometers Stop Working: A Look Into the Mechanics

Have you ever wondered why your speedometer suddenly stops working? From malfunctioning internal components to external mechanical interference, there are a variety of factors that might be causing the issue. In this article, we’ll take a look into the mechanics behind why speedometers can stop working and how to troubleshoot the symptoms.

Common Causes of Speedometer Malfunctions

From bad connections to faulty sensors, there are a variety of causes that can cause your speedometer to malfunction. Understanding the primary culprits can help you diagnose and potentially prevent other problems.

Inaccurate Calibration:

The speedometer might be malfunctioning due to incorrect calibration. Variable transmissions and differential ratios can cause a discrepancy in the speedometer readings, meaning that the speedometer doesn’t necessarily match the vehicle’s actual speed. Check the calibration of the speedometer against the actual speed to determine if the issue is with the speedometer calibration.

Faulty Wiring or Connections:

One of the most common reasons for a malfunctioning speedometer is a faulty wiring connection. It’s possible for corrosion or debris to build up on the internal wiring, which can prevent the speedometer from transmitting readings to the gauges. This problem can be fixed by cleaning the wiring and connectors.

Faulty Sensors:

Another issue might be with the speedometer sensor itself. These sensors work by detecting the rotations of the driveshaft or wheel, then sending the data to the speedometer itself. If the sensor is not functioning properly, the speedometer might not be able to register any readings. You can check the sensors by unplugging and reinstalling them or replacing them if need be.

External Mechanical Interference:

Another cause of speedometer malfunction is external mechanical interference. This can be caused by the ball joint of the steering wheel becoming disconnected or loose supports or bushings blocking the movement of the transmission. In these instances, it’s crucial to get the mechanical problem resolved before getting the speedometer fixed.

What to Do When the Speedometer Stops Working

  • If the speedometer does not seem to be functioning correctly, the first step is to check the wiring and connections. Make sure that all of the wires are properly connected and free of debris. You can also check the speedometer itself to ensure that it is reading correctly.
  • If all of the wires seem to be in order, then it’s possible that the issue is with the sensor or the external mechanical interference. To fix this issue, you need to identify the root cause so you or a professional can perform speedometer repair or replace any necessary parts.
  • It’s also possible that the speedometer is miscalibrated, meaning that it’s not accurately reading the actual speed of the vehicle. If this is the case, you can recalibrate the speedometer manually or visit a professional to do it for you.


There are a variety of factors that can cause a speedometer to malfunction. From damaged wiring, faulty sensors, and external mechanical interference, understanding the potential issues can help you diagnose and repair the problem quickly. In some cases, it might be an easily fixable issue, like a miscalibrated speedometer, that you can repair yourself. However, in more complicated instances, you might need to seek out a trained professional to make sure that the repair is done properly.

If you need help with speedometer calibration or other tech and automotive issues, Muritronix is the one to call. We provide complete repair solutions for all types of tech, appliances, and vehicles. From auto ECU repair to locksmith services and iPhone repair, Muritronix has the expertise and experience to get the job done. Contact us today for more information.