hair loss and skin rash

Question
what would cause ear inf. red raised rash .small black spots on skin.very foul breath

Answer
You need to get to the vet.  The one thing that comes to mind immediately is mites.  I also don't know how old your dog is but unless it's a very young pup, the bad breath indicates dental problems that need to be addressed.  How often do you brush his teeth?
What are you feeding him?

If ears are a chronic problem, go to EntirelyPets.com and order the Zymox Ear Cleaner and their ear meds.  (Just type in Zymox in their search box).  This stuff is amazing and handles all types of ear infection.  The cleaner & meds must be used together.

They have 2 meds.  One with hydrocortisone - one without.  You'd get the hydrocortisone formula if the ear is red, inflamed, swollen.
I keep both on hand.

I don't know what flea control or heartworm protection your dog is on but both Revolution and Heartguard prevent & kill mites.  To start on either there must be a quick blood test run to make sure he doesn't have heartworm.  No big deal and usually done in-house.
Delores