Fan control knob

[DrBroccoli]

So randomly last summer I was driving to a friends house and at a stop sign my car turned off, at the same time I turned my fan knob (with AC on) to 3. I was just like WTF?

Turned it back on no problems. Drove fine, no other issues like that to this day, except the byproduct of that random stall. When I put my fan knob of setting "3" it doesn't work. Just turns off (the fan) but 4 works at max power and 2 and 1 work at their respective levels.

Not really a huge issue but was wondering if anyone knew what it could be around here? I'm still in warranty so I'll take it in eventually if I have to, it's just my dealer is swamped right now and it was trouble enough getting my ignition fixed in one day.