The new service is the cornerstone of the company’s business strategy for connected cars. Onboard sensors gather data about on how the car is running. This information is relayed wirelessly to Nissan, helping the automaker estimate the timing of the car’s next engine tune-up or battery change. The price of the service has not yet been determined. But the company plans to keep the cost of upgrades for used cars affordable, with the aim of having the data link installed in around 30% of all Nissan vehicles already on the road, according to Vice President Kent O’Hara, who heads the after-sales business. The company hopes to capture more demand for car accessories and replacement parts through increased customer contact.