I have a 2002 Prius. When I start the car, at the beginning of the day. the ABS light comes on and the battery light comes on. Also, a high pitched screech. If I turn the car off and restart, it goes away. As I go from place to place running errands, each time I start the car, it is ok. It happens only when I start it for the first time of the day.
It's very common trouble when it comes to weak (dropped power) of your auxiliary 12V battery (do not confuse it with your main High Voltage battery). Please connect your 12V battery into car battery maintainer or simply replace 12V battery. Use search within this forum as members often post instructions which types of replacement batteries suit best. Optima is often popular for GENII, I used in Europe VARTA Blue. As long as polarization, size of the battery terminals and size of the battery casing fits your car, then should be no problem.
