Alternator/ Cruise Contol Strangeness

I thought I had two separate problems this week, but it turned out to be just one (I think). I've been near DFW, TX all week, I drove from CO to TX last Sunday. While driving to TX, my cruise control stopped working and I assumed I needed to order a new amp. On tuesday, while driving around locally, my alternator light came on (after driving through a fairly deep puddle). The next day my battery was dead so I found a local place to toss in a new alternator. The funny part is that my cruise control came back to life with the new alternator.

I'm guessing that the failing alternator wasn't putting out quite enough voltage for the cruise amp to work, maybe the amp is getting a little weak. I'm driving back to CO on saturday, it will be interesting to see how the cruise holds up. I'll hold off ordering a cruise amp for a while and see how it does with the correct voltage.

I just thought it was strange.