* Low Freon wasn't the only problem: While low freon *prevents* the compressor clutch from engaging (as a safety feature), it sounds like there was a more significant issue to begin with. Simply adding freon won't fix problems like:
* Faulty compressor clutch relay: This is a common failure point. The relay switches power to the compressor clutch. A simple test is to swap it with another relay of the same amperage (ensure you have the right amperage, check your owners manual or look at the relay itself) to see if the problem moves to that other component. If it does, replace the bad relay.
* Bad compressor clutch: The clutch itself might be worn out or seized. This requires replacement of the entire compressor clutch assembly, which is a more involved repair.
* Wiring issues: Check all the wiring related to the compressor clutch for shorts, breaks, or corrosion. This includes the power wire, the ground wire, and the connection to the pressure switch.
* Pressure switch: The low-pressure switch prevents the compressor from running if the refrigerant pressure is too low, protecting the system. If it's faulty, it might not allow the compressor to engage even with sufficient freon.
* Bad compressor: The compressor itself might be failing, and adding freon won't revive it.
What to do:
1. Check the pressure switch: This is the easiest thing to check and often overlooked. There's probably a diagnostic connector or port you can use a gauge to check pressure.
2. Check the relay: Swap it out with another similar relay as described above.
3. Check the wiring: Inspect all wiring going to the compressor clutch for any signs of damage. Pay close attention to connections.
4. Consult a repair manual: A service manual for your 1996 Eldorado will provide detailed diagrams and troubleshooting steps.
5. Take it to a professional: If you're not comfortable working on your car's AC system, it's best to take it to a qualified mechanic or an A/C specialist. Improperly handling refrigerant can be dangerous. They have the tools and expertise to diagnose the problem accurately and make the necessary repairs. Attempting to "jump start" the system can easily cause more significant damage.