The electric fans should only come on when engine is hot (above temp level) or when the ac or defrost is on. Turn your ac on and see if they start working
If I remember the Cadi's of that year the Cooling fans only turn on around 218 degrees and if the A/C is turned on they will only turn on when the high pressure reaches 198 lbs, and possibly only 1 fan will run at that time.
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