A couple quick thoughts: your fan may be bad. It's a two speed motor, and it could be it no longer works on the high speed. You can test this by grounding pin 17 on the CCRM when the car is on - the HI speed should come on. If it doesn't, probably bad fan. Another option may be that the Engine Coolant Temp (ECT) that feeds the ECU is bad - meaning maybe the car doesn't realize the fan should be on. The 94 GT has two ECTs - one feeds the gauge in the instrument cluster, and the other feeds the ECU. Lastly, your CCRM might be bad.
And the fan is supposed to come on when you turn on the A/C - so that's normal behavior.
