Car drivers are leaving phone numbers, addresses and even wifi connection details in their old cars, exposed to hackers, a study says.
When smartphones connect to cars via Bluetooth or USB, they sync a set of personal information so that users can listen to music, enjoy hands-free calls, and use GPS to get to their destination.
However, many users forget to erase this information before selling their car, which means it could remain there and be "given" to future owners.
Which? magazine revealed the error after surveying 14,000 car drivers who had sold their vehicle in the last two years.
The survey found that four out of five vehicle owners did not follow the instructions in the car manual to remove their data and restore the vehicle to factory settings before selling it.
It also revealed that one in two drivers (51 percent) had not attempted to desynchronize their phone with the car before selling it.
And a third (31%) took no action to remove their personal data before leaving their vehicle.
Just over half of respondents (54 percent) said they had synced their phone with their car.
It seems that car drivers don't have enough information about what is collected when they sync their phones or download an app and the importance of erasing the data.
Which? editor Harry Rose said: “If cars are not treated in the same way as a smartphone, tablet or other connected devices when it comes to data security, car drivers risk having their personal information sold along with their car.
"Manufacturers need to do much more to prioritize customer privacy so that drivers fully understand how much data vehicle and how to delete that information to eliminate these risks."
