How do you recharge ac system 2005 cadillac dts?

To recharge the AC system of a 2005 Cadillac DTS, first ensure the vehicle is off, then connect a refrigerant canister with a gauge to the low-pressure service port located on the AC line. Start the engine and turn the AC to the maximum setting. Open the canister valve and monitor the gauge to avoid overcharging, adding refrigerant until it reaches the recommended pressure. Finally, disconnect the canister and check for proper AC operation.