IF we are talking about the fans in the air conditioning system (basement models), there is usually a 'Fan" switch on the thermostat that can be turned on and will operate the inside fans at low and high speeds. Just listening from outside or inside should tell you if they work as expected without the compressor noise interfering. The airflow out the vents would help too. If you have the means, you could measure the current draw and check that against the specs.
They cannot be observed visually otherwise. The OP did not specify what prompted him to check the 'fans' and that might have helped in the diagnosis.