I had the same problem with my 94 LHS.

Do not exactly remember the exact fix but it is related to the AC circuit.

There is a pressure sensor that tells the computer the AC is in demand. During this condition the computer tells the fans to run to cool the condenser.

I remember replacing a pressure switch and it's a very smart set up. The switch pushes on a Schrader valve so you don't lose freon when you unscrew it.