Excess speed is one of the three main causes of traffic accidents after distraction and alcohol abuse. And since no one is supposed to disregard the law, the speedometer is precisely present in all cars to remind you to order. Thus it helps determine the vehicle’s speed and indicates the distance traveled by the vehicle along the road. But you certainly noticed a surprising contrast: Why does the GPS never match the speed displayed on the dashboard?
Why isn’t your car’s speedometer showing the actual speed?
The speedometer collects data from a sensor located in the gearbox. This sensor is part of an electronic system that sends a signal to the speedometer by means of electrical impulses. The faster the transmission rotates in the car, the faster the electrical impulses are transmitted and the faster the instrument panel indicates.
In fact, manufacturers voluntarily include this margin of error to cover their backs in the event of an accident. Thus, the speedometers are inaccurate for the safety of drivers. By driving at a low speed, they are avoiding and avoiding speed. Regardless of your car’s make or model, this upward margin of error is very common. In general, the counter speed cannot be lower than the actual speed. Specifically, there should be an upward margin of error of 10% plus 5 km/h. Note that this difference between the actual speed and the displayed speed is closely related to speed cameras on the road. By increasing it voluntarily, it is above all a guarantee of your safety: therefore, you will not drive faster than the authorized speed!
Other criteria may come into play
There are also other factors, among others, such as tire pressure or vehicle weight, that explain why the speedometer may not give the exact speed. In fact, it calculates speed by measuring the rotation of the wheel and transmission shaft using a sensor located in the gearbox. Thus, the condition of the tire (whether it is worn or not, if the pressure is correct, etc.) can modify the calculation of the real speed of the car by up to 2 km / h.