How to Check a Car’s Mileage with OBDeleven

How to Check a Car’s Mileage with OBDeleven
Looking to add a new set of wheels to your garage? Before you sign on the dotted line, make sure to check the mileage! Think of it like a detective story – the mileage is the most important clue that helps you piece together the vehicle's history.  

A low mileage car may indicate that the previous owner was a weekend warrior who took great care of their ride. On the other hand, a high mileage car may indicate a road warrior who put a lot of miles on their vehicle. Either way, checking the mileage will give you a better understanding of your car, its overall condition, and potential issues. This way, you'll be able to make an informed decision when buying your next car. 
Note: Be aware of odometer fraud – the practice of rolling back the odometer to show a lower mileage. Learn more about odometer rollback and how to avoid it in our detailed article.

There are a few ways of determining a car's true mileage, let's go over some of the most popular methods. Though, it's important to note that the methods we’ll talk about for checking a vehicle's mileage may not work on all vehicle models.  

Different car models have different ways of storing mileage information, which may not be easily accessible in all vehicles. These methods can be used only with VAG vehicles that use the UDS protocol, which started production in 2008 and become widely used in 2012.

Checking Car Mileage with Live Data

Using the Live Data feature, you can check the mileage of different control units. Usually, mileage can be found in the Engine, Transmission (if available), and Dashboard control units. Depending on the vehicle, mileage can also be stored in other control units.

When you open the Live Data function, you can search for parameters with keywords such as distance, mileage, km, etc. in their name – vehicle distance driven, transmission mileage, and distance. After checking the mileage from at least a few control units, you can then compare the results. If the mileage differs by a few hundred or thousands of kilometers between control units – it's normal. But if one of the control units has significantly lower or higher mileage than the others, the unit has likely been replaced.  

Also, if the Dashboard mileage is noticeably lower than in the other control units, the Dashboard mileage may have been changed without bothering to change the mileage on the other units. Normally, the Dashboard should have the highest mileage of all control units. 
Further reading: How to read OBD live data

Working Hours 

For some vehicles, it's possible to find approximate working hours using the Live Data feature. These can be stored in the Steering Assistance, Media (screen time), and other control units. Once you know the number of working hours, divide the mileage on the Dashboard by the number of hours to get the average speed of the car.  

The normal average speed is around 50 km/h. If the calculated average speed is significantly lower than 50 km/h, this may indicate a possible falsified mileage or can possibly mean that the car has been driven in urban areas. As a result, this can lead to a higher chance of wear and tear. Otherwise, a higher average speed may indicate that the car has been driven on long-distance highways.   

Recent Events 

Another way to check the validity of your car's mileage is by checking the recent events in control units' Live Data. This function can show you when and at what mileage certain events occurred. For instance, in the Engine control unit, you can find mileage saved in the various Live Data tabs, such as the Number of prevented stop processes or Number of requested start processes.  

In the Brakes control unit, this information can be found under the Counter steer control and Tire pressure monitoring display tabs. This stores up to four last adaptations of the tire pressure monitoring system, as well as the mileage recorded when messages were shown, so we can sometimes see up to a few years of mileage history if the car has the feature.  

If you see that the mileage recorded in one of the events is higher than the Dashboard mileage, the dashboard mileage has likely been changed. This method is effective for newer models in cases when the mileage has been adjusted recently.  

Freeze Frame  

Once you've scanned the faults, you can see the mileage at which the faults were recorded. If the mileage in the fault's freeze frame is higher than the mileage displayed on the Dashboard, the mileage in the dashboard has likely been adjusted. However, this method only works if there are faults that occurred before the mileage adjustment and have not been deleted.  
Further reading: What is freeze frame data?

Wrapping Up   

A mileage check is like solving a mystery – it's an essential step when buying a used car. With the power of OBDeleven, you can easily access the information you need to piece together the story of the car's past.  

Whether it's checking the Live Data in different control units, calculating the average speed, or checking for errors in the Freeze Frame – you'll have all the tools you need to uncover the truth about your car's mileage. So, before you sign on that dotted line, use OBDeleven to make sure you're getting the best deal possible on your next ride. 
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