Just purchased 2007 Prius Touring model w/ Package 6. Wonderful car. Quick question: Is it normal to hear a buzzing/rattling noise when stopping at low speeds or starting at low speeds? It seems to be coming from the drivers side. Doesn't happen every stop/start. Thanks for your help.
Yes, it is normal. The pump maintains pressure in the hydraulic brake system. An electric pump is necessary because a vacuum booster pump would not work, since the engine is not always running.