Conner ran for 145 yards and a touchdown on 23 carries before sustaining the shoulder ailment. He left Heinz Field with his right arm in a sling. Conner exited the game with the injury near the two-minute warning.
Steelers running back Benny Snell is also being evaluated after picking up a knee injury during the 27-14 victory Monday in Pittsburgh.
"James Conner has a shoulder/AC, and is being evaluated," Steelers coach Mike Tomlin told reporters. "We will know more about those guys. I will update [reporters] Monday at our normal press conference."
Conner has scored in four consecutive games. He had at least 100 yards from scrimmage in three of his last four contests.
"He came out hot early and it really kind of sparked us as an offense," Steelers quarterback Mason Rudolph said of Conner. "Coach Tomlin has been talking all week about securing those 10-yard runs, and we need more of them. We're making ourselves more of a complete offense, and I think we really challenged our offensive line, which had been doing great in that area all week.
"James did a good job. He's playing up there at the top of the competition of running backs in this league. He's a physical guy. He really provided us with a spark [Monday]."
The Steelers (3-4) host the Indianapolis Colts at 1 p.m. EDT Sunday at Heinz Field. Former practice squad player Trey Edmunds in the only healthy running back on the Steelers' roster.