Here are the steps on how to locate the low pressure AC port on a 2004 Jaguar S-Type:
1. Open the hood of the car.
2. Locate the air conditioning compressor. It is a black, cylindrical object located on the front of the engine.
3. Find the low pressure AC port. It is a black, plastic fitting with a blue cap located near the compressor.
If you are unable to find the low pressure AC port, refer to the owner's manual for your vehicle.