SAN FRANCISCO — As new employees were brought into Apple’s secret effort to create a self-driving car a few years ago, managers told them that they were working on the company’s next big thing: A product that would take on Detroit and disrupt the automobile industry.

These days, Apple’s automotive ambitions are more modest. The company has put off any notion of an Apple-branded autonomous vehicle and is instead working on the underlying technology that allows a car to drive itself. Timothy D. Cook, the company’s chief executive, said in an interview with Bloomberg in June that Apple is “focusing on autonomous systems.”

A notable symbol of that retrenchment is a self-driving shuttle service that ferries employees from one Apple building to another. The shuttle, which has never been reported before, will likely be a commercial vehicle from an automaker and Apple will use it to test the autonomous driving technology that it develops.

Five people familiar with Apple’s car project, code-named “Titan,” discussed with The New York Times the missteps that led the tech giant to move — at least for now — from creating a self-driving Apple car to creating technology for a car that someone else builds. They spoke on the condition of anonymity because they were not authorized to talk publicly about Apple’s plans.