Blower in Attic not running

Question

Hi,
I have a blower / heating unit in my attic with the compressor units outside.  Recently, both fan units in the attic went out.  The circuit breaker is live, and the electrical outlets in the attic servicing both units are hot.  My problem is this:  When I turn on the thermostat to the AC, the outside compressor unit runs.  However, the blower unit in the attic does not.  It does not matter whether I set the thermostat to heating or cooling, the blower unit in the attic does not run.

Any suggestions?

Thanks in advance