Hello my name is Dave.
Unfortunately these systems are difficult for the DIYer to work on regardless of their level of knowledge due to the fact that whenever there is a fault with the system you would need an actual scanner to reset the system because it will set what is commonly referred to as a "hard code" that will not clear by disconnecting the battery. That being said it sounds like there is an issue with the air distribution module however like I stated it would be very difficult for me to be able to guide you to finding the problem without a scanner that is capable of communicating with the 4Matic system. If by chance you have access to a scanner that can do this I would be more than happy to guide you in the diagnosis as I have extensive experience with these systems. If you do have to take it to a repair shop I would highly recommend making sure they are familiar with the system as most issues with the system are not usually as complicated as some techs think they are.
Thursday, February 21st, 2019 AT 4:46 AM