Hyundai Repair: 03 Elantra AC smell, climate control system, musky smell

Question
My AC has a musky smell when running the AC. My car has about 140K miles. The AC works great otherwise. What can I do to rid of this most likely a mildew smell?

Answer
The easiest way to combat the odor is to run air freshener through the system.  Take not of the holes in the plastic trim below the outside of the passenger side of the windshield.  It's in this location that the fresh air enters the climate control system.

Gather an aerosol air freshener of your choice, start the vehicle, turn the blower fan to high speed, the air intake control to fresh air, and the temperature control to full hot.  Then spray the air freshener in through the holes mentioned above.  This will disperse the air freshener throughout the climate control ductwork.