Sounds like you have a bad engine coolant temperature sensor. When it goes bad, then engine management system goes into a fail safe mode and assumes the temperature is too hot, which means the aux fans come on at high speed and the A/C compressor is locked out.

You can use your A/C control panel to pull real time data and fault codes too. Search this forum for "A/C codes" or something similar and you will find it.

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"It's not about how fast you can go, but how well you can go fast."

Bob in Richmond

'97 S320 (LWB), Ruby Red Metallic, 73k miles
'97 S420V, Smoke Silver Metallic, 155k miles