Anyone know anything about range hoods?

[Maple Leafs]

We've got one of those nice Chinese-style range hoods that came with our house (a Pacific AC3100). We don't get much use out of it; we'll occasionally throw it on when cooking something smokey, but that's about it.

Today, it started turning on by itself. It's not the fans. Rather it's the little motor next to the cleaning reservoir. It seems to want to fire up on its own; there's no feature for programming or scheduling the cleaning or anything like that. It doesn't actually do anything other than buzz, but it's trying.

My general rule of thumb is that when appliances start to trying to achieve sentience, they get unplugged and replaced. I'm just wondering if there's something I'm missing here, since I don't know anything about range hoods or how they work.