Chevrolet Repair: A/C Fan, loose wire, loose connection

Question
It's not a Chevy but an oldsmomile 88 Royal.
I figured that the question may be basic and applicable.
Question: 1990 Olds, 85,000 miles, A/C fan comes on a few moments after driving. Almost seems as though there is a loose connection?  Once on A/C remains on until the engine is shut off. How does one access to check to find a loose wire?
Thanks,
Bob  

Answer
I am guessing that you don't use your A/C?
Is this the only fan or do you have 2?
Look for a cooling fan relay that might be bad.
Should be a black square box 1x1 inches in diameter located normally on the top of the firewall in the rear part of the engine compartment.