Electrical System problem 2006 Yaris

[Ivriniel]

Last week, I started having trouble with the electrical system on my Yaris. In the morning I'd get in the car and the battery light would be on. I'd drive for a while, and then it would turn off.

Since then, the amount of time I've had drive before the light turned off has increased. Today I drove for a hour, and the light stayed on the whole time.

Today I took the car in for scheduled maintenance at the dealership and they had a look at it. They say that my alternator is going and I need a new one. They also said that the YARIS has a new style of alternator and they don't recommend rebuilding it because it wouldn't last.

I've had my Yaris for 3 years and 6 months, so it's out of warranty. It has 55 000 KM (34 000 miles) on it.

Admittedly, I don't know a tonne about cars, but I know that the alternator shouldn't be dying already.

It also seems strange that I haven't noticed any of the symptoms of a bad alternator: the car has had no trouble turning over, and the wipers, radio and lights all continue to work even when the light is on. I haven't had to boost it at all. If it weren't for the light coming on, I wouldn't think I had a problem.

So basically, I'm asking what people think. Does this seem likely?

Thanks.