Toyota Repair: Odor in A/C - 1999 4 Runner, air mode, drain hose

Question
There is an odor coming from my A/C I believe and it smells like dirt or old soil.  Is there any way to clean the A/C?  Spray?

Thanks,
Vaughan

Answer
The odor is caused by excessive moisture in the evaporator housing, this can be caused by a clogged evaporator drain hose, check it by running the a/c for a while in the driveway or garage and see if there is water dripping fom the drain hose on to the ground, if not the drain hose is either disconnected or clogged and the evaporator housing is filling up with water, if it's disconnected the water normally runs into the passenger compartment and will cause the floor on the passenger side to be wet.
There are some commercially available a/c deodorizer kits, check with a local auto supply store.
Another reason may be that the a/c is never used in the fresh air mode and is always used in the recirc mode which can cause fungus and mold to form on the evaporator core.