Do I present my common access card at the checkpoint to access the TSA PreCheck® lane?

No. All members of the U.S. Armed Forces must include their DoD ID number in the Known Traveler Number field when making flight reservations and a TSA PreCheck® indicator must be visible on your boarding pass. The airlines will print a TSA PreCheck® indicator (such as TSAPRECHK, TSA PRE, or TSA PreCheck®) on boarding passes to help you recognize when you are eligible for TSA PreCheck® on your flight.

You cannot access the TSA PreCheck® lane by presenting your CAC or other documentation.