[Kraz43series]

Hello guys

A week ago I purchased a 2006 325xi with 127k. The dealership I got it from gave me a 90 day warranty which when reading it seems like it should cover stuff. The other day my 4x4 light came on. I called the dealer yesterday to ask for the service dept she said they would call me back and never did. So last night I dropped my car off to my trusted Indy mechanic.
Just got a call from him this morning saying it's the transfer
Unit and he'll call me back later. So my question is will my warranty cover this? Do I call Proguard or do I take it back to the dealer? Will I get reimbursed?

Thank you