There are several common causes for a speedometer to stop working. Typically, these malfunctions are caused by an issue with a car's wiring, a broken gear in the speedometer system, a speed sensor issue or a faulty engine control unit (ECU).Know More
According to the experts at Seva Call, a faulty speed sensor is the most likely culprit in the case of a malfunctioning speedometer. Often covered under warranty, the speed sensor is located near the front axle and calculates the speed of the vehicle.
Another common and easy-to-fix issue could be a broken gear on the speedometer unit itself. Autos.com suggests that after diagnosing an issue with the speedometer unit, the vehicle owner can purchase replacement components from the dealership where the car was purchased, at certain body shops or on the Internet.
A malfunctioning speedometer may also be due to damaged wiring. Wiring is vulnerable to water damage and can cause fuses to blow. If the problem appears during wet weather especially or if the car has been exposed to excessive water, there is a good chance that this could be the issue.
Lastly, many automobile problems can be traced back to a malfunctioning ECU, which is the main computer that manages many of the car's processes. If the ECU is not working, it is possible that it is preventing the speed sensor from reporting the speed to the speedometer. A broken ECU breaks this link between the two components and could cause an issue.Learn more about Car Parts & Maintenance
Bigger tires will cause your speedometer to register a speed that is slower than your actual speed. For example, if your speedometer says 35 miles per hour on 20-inch diameter tires, changing to 23-inch diameter tires will make your true speed 40.25 mph, even though your speedometer will still show 35 mph.Full Answer >
A car speedometer measures speed: how fast the car is moving. Speedometers measure speed in miles per hour or kilometers per hour. Some gauges display both readings.Full Answer >
The most likely reason a speedometer stops working is a broken gear. Finding the problem involves removing the speedometer assembly from the vehicle and locating the problem piece. Replacements are available at dealerships, auto parts stores and online.Full Answer >
A speedometer can be repaired at home if it is making an unusual noise and if the needle is slow or does not move because of a broken gear or other component. However, any electrical problem with the unit needs to be repaired by a specialist.Full Answer >