What Causes the Air Conditioning Compressor in a Buick Regal to Stop Working?

[GrantLee]

Buick Regal air conditioning compressor not working may be caused by the following reasons: 1. Compressor failure: Severe internal wear of the compressor leads to inability to function properly. Its primary role is to compress and circulate refrigerant, which means the compressor operates at high speeds continuously, making this one of the reasons for compressor malfunction. 2. Faulty temperature sensor or pipeline pressure sensor. 3. Lack of refrigerant (system leakage). 4. Air conditioning AC not turned on or insufficient temperature adjustment. 5. Air conditioning control module failure.

[JulietteMarie]

Last time I drove the Buick Regal, I encountered an issue with the AC not cooling. The most common reason for the compressor not working is insufficient refrigerant. After driving the car for three to five years, the refrigerant can naturally deplete or there might be minor leaks in the piping. Another possibility is a malfunction with the compressor's electromagnetic clutch—if that part fails, it won't engage and start at all. Additionally, if the pressure switch detects abnormal system pressure, it will automatically cut off the compressor to protect the system. By the way, I suggest you open the hood after ignition and listen for the clicking sound of the relay engaging. If there's no reaction at all, you should check the AC fuse in the fuse box. In this weather, having no AC is unbearable. What I usually do is turn off the AC, wait a few minutes, and then restart it to see if it can recover on its own.

[DanielLynn]

If your AC compressor stops working, don't rush to the repair shop. First, check a few simple things yourself: see if the AC button indicator light is on - if not, the central control panel might be malfunctioning; pop the hood to inspect the drive belt tension, as a loose or slipping belt on a Buick Regal can prevent the compressor from running; then feel the temperature of the two aluminum AC lines - if there's no temperature difference at all, it's likely low on refrigerant. A friend's car had a clogged expansion valve, causing system pressure imbalance and automatic compressor shutdown. With the recent rainy season bringing high humidity, remember to regularly use the external air circulation to ventilate and prevent wiring oxidation issues.

[DelJordan]

The compressor not working is mostly due to electrical system issues. First, check the 20A air conditioning fuse in the fuse box under the driver's seat—I just replaced that little transparent piece last month. Then inspect whether the compressor relay is engaging. Use your phone's flashlight to check the black box under the hood, pull out the relay and shake it to listen for any loose parts inside. Another easily overlooked point is the temperature sensor—if the small probe behind the left vent on the dashboard fails, it can misread the temperature. Finally, try turning on the rear window defroster, as this function forces the compressor to start.