1. Unscrew the threaded cap of either of the two service valves.
WARNING: Wear safety glasses when working.
2. Carefully press the tip of the valve core with a thin, long-tip screwdriver and bleed the refrigerant from the system.
WARNINGS: Release refrigerant from the air conditioning system outdoors or in a well-ventilated area.
Coolant turns into a gas at atmospheric pressure. Release coolant from the system in a very thin stream. When releasing coolant, some oil mixed with it may splash out. Place a cleaning cloth around the service valve to protect the engine compartment from contamination.