2005 Chrysler 300 can this be fixed manually?

I was drving the car and the engine light came on along with a }z{ similar to this, came on. My step son about a week late gave me a tune up change the oil, replaced filters (oil, air) and plugs. Now it is running rough. I have a CARMD and hooked it up it said the comprehensive Component Monitor has detected a malfunction in the idle air control cystem that caused the engine speed to be higher than the target idle speed for a predetermined period of time for the driving conditions present when the code was sent. The idle air control system is used on fuel injected engines to help provide a smooth idle under all operating conditions. Now does this have to be taken to a dealer or can a mechanic fix it, or can it be fixed manually from the car? Thanks, Oh it wasnt doing this before the tune up was done but I guess you have to move a lot of stuff to get to anything in the motor.