How do you add refrigerant to a 1990 Cadillac brougham?

To add refrigerant to a 1990 Cadillac Brougham, first locate the low-pressure service port, typically found on the larger diameter aluminum line between the compressor and the evaporator. Attach a refrigerant gauge and hose to the port, ensuring it’s securely connected. Start the engine and turn on the air conditioning, then gradually add refrigerant while monitoring the pressure on the gauge to avoid overcharging. Always follow safety precautions and consider consulting a professional if you're unsure.