We own two 2006 Prii, and the older one (62,000 miles) did this over the weekend: 1. The engine, brake, and emergency lights all came on simultaneously. 2. Before we could get it to a dealership, the Energy screen showed no bars on the battery. No blue arrows ever showed battery being charged, whether braking or accelerating. 3. Engine sounded like it was racing, even when stopped. Exhaust fan was on next to the rear right seat. Barely any power at all with the accelerator. 4. Taking foot off accelerator did not slow the car down! Car maintained speed (increased speed downhill) with no accelerator pedal depression (this is when I thought I might wind up on the news). The dealership is telling me it's a hybrid battery malfunction, and they're replacing it (free under warranty). Though it's comforting that it's under warranty, it still kind of freaks me out that at 62,000 miles I'd have to replace the battery. Anyone else have a battery fail? At what mileage?