Carmakers use data to alert us when something needs repair or when our cars need to be taken in for service. What they don’t tell us is that by controlling our data, they can limit where we get that repair or service done. For almost a century, car and truck owners have been able to take their vehicles to whichever shop they choose and trust for maintenance and repair. That may be changing.

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Because of the increasing complexity of cars and the Internet of Things, data is critical to repair and service. When carmakers control the data, they can choose which service centers receive our information. They’re more likely to share our data exclusively with their branded dealerships than with independent repair shops, which could have the edge in price and convenience. However, independent repair shops currently make 70 percent of outside warranty repairs throughout the country.

This is a different facet of the privacy conversation. Our anxiety about data typically focuses on what happens when information is shared with those we don’t want to see it. But what about when information is withheld from those we do want to see it?

Imagine visiting a medical specialist and learning he can’t get access to the medical history that your doctor maintains, or having a financial adviser acknowledge that neither of you can see your accounts unless you pay a fee. It’s alarmingly easy to imagine carmakers’ charging fees to independent repair shops that need access to vehicle data to service a vehicle purchased for tens of thousands of dollars. That fee will lead to vehicle owners’ paying higher repair prices just so that technicians can obtain the data.

There are more than 180,000 independent repair shops across the country; most have all the tools needed to work on today’s connected and complex cars, and most of today’s highly trained service technicians can perform anything from basic tuneups to sophisticated electronic diagnostics. But without access to car data, they’re working blindfolded, unable to see the diagnostic information they need.

The solution is simple. The only person who should control car data is the car owner (or lessee). He or she should be aware of the data the car transmits, have control over it and determine who can see it.