The clutch is a two wire plug, +/-. Check for power. Use a digital voltmeter across the compressor plug. 0 ohms means the clutch is fried.

Mine has a bad switch. I know because the fan does not turn on right away. Once the engine is hot, it doesn't matter. Engine cooling keeps the fan running. It's a bit annoying on hot days. I don't mind it for now. I start driving right away and cooling begins. I have not replaced the switch since the system has to be evacuated. I'd rather not disturb it until necessary. Once it's moving or the fan is running, temps go down to 42F!

If you have a 12V power source, you can actuate the clutch. Or use a bidirectional scanner. With the engine off and activation, you should hear the clutch engage. With the engine off, can you spin the compressor by hand? Likely, the clutch is worn out or slipping.

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'06 X5 3.0i - bought @143,123 miles (12/26/20)