A number of things contribute to a properly operating A/C. The purpose of this thread is to help you get the type of help you need based on your A/C issues.
- -THE COMPRESSOR MUST ENGAGE. If the compressor clutch does not engage, we need to find the reason. The #1 cause for no compressor clutch engagement is a lack of refrigerant (leak). Other causes are blown fuses, PCM strategies, faulty modules, or poor connections. http://www.fordforumsonline.com/forum/heating-air-conditioning-cooling-systems/303-test-c-cycle-switch.html#post1485 or http://www.fordforumsonline.com/forum/electrical-lighting/128-howto-check-your-fuses.html?nojs=1#links or http://www.fordforumsonline.com/forum/electrical-lighting/144-howto-check-relay.html?nojs=1#links or http://www.fordforumsonline.com/forum/electrical-lighting/90-check-ground.html?nojs=1#links To learn more about Compressor Clutches, read this: http://www.fordforumsonline.com/forum/heating-air-conditioning-cooling-systems/7601-compressor-clutch.html
- -The system must be full of refrigerant. If the compressor is cycling excessively (click on, click off, click on, click off), The A/C system is most likely low on charge. Typically there is a leak in the system that has depleted the refrigerant. You might consider the use of dye to help find the leak. Often the aid of an A/C professional is needed when finding and fixing leaks. http://www.fordforumsonline.com/forum/heating-air-conditioning-cooling-systems/155-c-clutch-clicking-off.html
- -There must be air flow both inside and under the hood. The A/C condenser needs air moving across it at any time the A/C is active. If the electric cooling fan(s) or fan clutch are faulty, A/C performance will be diminished, especially at an idle. The inside blower fan must also be working to distribute the cold air.
- -The temperature blend door must be positioned correctly. If the A/C system is full of refrigerant and operating correctly, yet heat is being delivered, the blend door should be suspected. To a lesser degree, the heater valve might also be faulty.
- -The air distribution system must work properly. If all the air flow is only delivered at the defroster vents, the vacuum source needs to be investigated. A faulty mode door vacuum diaphragm can cause insufficient air delivery to the dash vents, while other air flow remains good.