a/c fan problem on 1995 Buick Riviera

had a/c on when a small vapor appeared in the defrost the fan does not operate at all...all fuses checked and seem okay...air will come into car on economy setting but not other time...compressor is operating okay...what could be the problem and where is the fan located...could not see it looking at firewall

Asked by for the 1995 Buick Riviera
The fan is behind the dashboard, and not easily visible. This sounds like the fan motor or the blower motor resistor may have failed, and the vapor you saw may have been smoke from one of those items. I would get it checked out very soon if it was indeed smoke, that can turn into something worse.
1 more answer
Second thing may be a water leak, either windshield or heater core, rusted the fan and the vapor is water vapor from sitting water.