2021 Cadillac CT5

Programming Guide for 2021 Cadillac CT5 Smart Keyless Entry Remote Fob

Each 2021 Cadillac CT5 can have up to eight remote keys registered to the vehicle. Follow the appropriate method below depending on whether you have two recognized keys or none.

Programming with Two Recognized Remote Keys: If two functioning remote keys are available, you can program a new remote key yourself using the vehicle’s onboard system.

  • Step 1: Ensure the vehicle is in RUN (engine off, but electronics active).
  • Step 2: Place both recognized remote keys on the front passenger seat.
  • Step 3: On the Driver Information Center (DIC), navigate to the “Remote Key Relearn” menu and select it. The DIC will display “READY FOR REMOTE #3, 4, 5,” etc.
  • Step 4: Place the new remote key into the rear cupholder.
  • Step 5: Press the ENGINE START/STOP button. The DIC will confirm when the remote key has been learned.
  • Step 6: Remove the new remote from the cupholder and press the LOCK or UNLOCK button to complete registration.
  • Step 7: To program more remotes, repeat Steps 4–6 for each additional remote.
  • Step 8: Once finished, press and hold the ENGINE START/STOP button for approximately 12 seconds to exit programming mode.

Programming Without Recognized Remote Keys: If no recognized remote keys are available, the vehicle requires use of a diagnostic tool to perform key programming.

Important: This vehicle does not support onboard key programming without at least two working remotes. In this case:

  • Step 1: Ensure all new remote keys are present inside the vehicle.
  • Step 2: The vehicle must be accessed through the driver door using the mechanical key blade if the smart key is unavailable.
  • Step 3: Turn the ignition on using the Start/Stop button without pressing the brake.
  • Step 4: A certified technician must connect a diagnostic scan tool to the vehicle's onboard port.
  • Step 5: Using the tool, access the key programming menu and follow the prompts to erase or add keys.
  • Step 6: After programming, test each remote by pressing LOCK or UNLOCK and starting the engine.
  • Step 7: Repeat the diagnostic programming process for each additional remote if more are being added.
  • Step 8: Confirm all remotes function as expected, then secure the key blades and return them to their fobs.