I have a 2001 Toyota Prius with about 249000 miles... The red triangle with the exclamation in the car symbol comes on at irregular times while driving the car. Sometimes it loses power, sometimes it accelerates, sometimes it keeps working, but the light stays on. When we turn the car off 4 times the triangle light goes away and the check engine light comes on. The first time this happened we found nesting material from a small rodent in the engine compartment. We cleaned it out and the lights went away, but we took it to a dealer anyway and they got no information. This has happened several times since then and the info the dealer gets is that a cell in the big battery is losing charge, but when they check the individual cells they are all fine. They say we need a new battery even though the cells seem to be fine. This battery is less than 3 years old and has about 30,000 miles on it (this is our second battery - the first one lasted 10 years and more than 200,000 miles). Anyone have any ideas.