Why is my engine speedometer not working?

If your engine speedometer is not functioning properly, it could be due to a variety of reasons. The speedometer is a critical component of your vehicle's dashboard, providing important information about your driving speed. In this article, we'll explore the common causes of a malfunctioning speedometer and provide guidance on how to troubleshoot and resolve the issue.

Common Causes of a Faulty Speedometer

There are several potential reasons why your engine speedometer may not be working correctly:

• Faulty Speedometer Sensor: The speedometer relies on a sensor that monitors the rotation of the vehicle's wheels or transmission. If this sensor is malfunctioning, it can cause the speedometer to display inaccurate or no readings.


• Wiring Issues: The speedometer is connected to the vehicle's electrical system through a series of wires. If there is a break or short in the wiring, it can disrupt the signal and prevent the speedometer from functioning properly.


• Mechanical Failure: The speedometer itself can experience mechanical issues, such as a broken gear or a stuck needle, which can prevent it from accurately displaying the vehicle's speed.


• Odometer Tampering: In some cases, the speedometer may not be working due to odometer tampering, where the vehicle's mileage has been intentionally altered, which can affect the speedometer's accuracy.

It's important to note that a malfunctioning speedometer can be a safety concern, as it can make it difficult to maintain the appropriate speed and comply with traffic laws. If you notice any issues with your speedometer, it's best to have it inspected and repaired as soon as possible.

Troubleshooting and Repair

If you suspect your engine speedometer is not working correctly, there are a few steps you can take to diagnose and address the issue:

• Check for Error Codes: Many modern vehicles have on-board diagnostic systems that can detect and report issues with the speedometer and other components. Consult your owner's manual or use a diagnostic tool to check for any error codes related to the speedometer.


• Inspect the Wiring: Visually inspect the wiring connecting the speedometer to the vehicle's electrical system. Look for any signs of damage, such as frayed or loose connections, and address any issues you find.


• Test the Speedometer Sensor: If the wiring appears to be in good condition, the issue may be with the speedometer sensor. You can use a multimeter to test the sensor and ensure it is providing the correct signal to the speedometer.


• Replace the Speedometer: If the sensor and wiring are functioning properly, the speedometer itself may need to be replaced. This is typically a job for a professional mechanic, as the speedometer is often integrated into the vehicle's dashboard.

Addressing a malfunctioning speedometer is important for both safety and legal compliance. By following these troubleshooting steps and seeking professional assistance if necessary, you can get your vehicle's speedometer back in working order.

How much does it cost to fix a speedometer?

The cost to fix a speedometer varies from $50 to over $400, depending on the specific problem, your car's make and model, and the shop's labor rates. Simple fixes like replacing a speedometer cable or gear can cost between $50 and $100, while replacing a speed sensor typically ranges from $100 to $200. More complex issues, such as a faulty instrument cluster, can cost between $150 and over $400, with newer electronic versions potentially costing up to $600 or more. 
Common speedometer repair costs

• Speedometer cable replacement: $50–$100
• Speedometer gear replacement: $50–$100
• Speed sensor replacement: $100–$200
• Instrument cluster repair: $150–$400+ (can be higher for luxury vehicles or electronic clusters) 

Factors that influence the cost

• The specific part needed: The cost will be different for a simple cable vs. a complex sensor or instrument cluster. 
• The make and model of your car: Repairs for luxury or high-end vehicles are often more expensive than for standard cars. 
• Labor rates: The hourly rate charged by the repair shop will affect the final price. 
• The complexity of the repair: More complex issues require more diagnostic time, which increases the cost. 
• Warranty coverage: If the repair is covered by a warranty, you may only need to pay for parts or a portion of the cost, but you will likely be limited to using a dealership. 

What would cause the speedometer to stop working?

There are many possible reasons why your speedometer might not be working. These include damaged or faulty speed sensors, compromised instrument clusters, gearbox problems, faults in connections and wirings, sensor calibration issues, and vehicle speed sensor (VSS) failure.

Is there a fuse for your speedometer?

Yes, modern speedometers are electrical and have a fuse, but older, mechanical ones do not. The specific fuse is for the instrument cluster or a related circuit and is located in either the interior or under-the-hood fuse box, depending on the vehicle. You should check the fuse box diagram in your owner's manual or on the fuse box cover to identify the correct fuse.
 
This video shows how to check fuses for the speedometer and odometer: 39sconquryourfear & do it urselfYouTube · May 7, 2015
How to check the fuse

1. Locate the fuse box: This is typically in the passenger-side footwell or under the hood. 
2. Find the correct fuse: Consult your vehicle's fuse box diagram to identify the fuse for the speedometer or instrument cluster. 
3. Inspect the fuse: Pull the fuse out and hold it up to a light to check if the thin metal wire inside is broken. If it is, the fuse is blown and needs to be replaced. 
4. Replace if necessary: If the fuse is blown, replace it with a new one of the same amperage rating. Never use a higher-amperage fuse. 

Other potential issues

• Speed sensor: If the fuse is intact, the problem may be the speed sensor itself. 
• Wiring: Inspect the wiring and connectors to the speed sensor for damage, corrosion, or looseness. 
• Instrument cluster: In some cases, the issue could be with the instrument cluster itself. 

This video shows how to check fuses and replace a blown fuse in a Chevrolet Silverado: 35sElectrical Car Repair LIVEYouTube · Jun 24, 2023

Can you drive a car if the speedometer is not working?

Driving with a faulty speedometer can also have legal consequences. In many regions, it's illegal to operate a vehicle with a broken or inaccurate speedometer. If you're pulled over and found to have a non-functioning speedometer, you could face fines or penalties.