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Q: Hybrid has a rough time starting

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My new 2012 Toyota Prius has a problem starting up. At first I thought it was just the button that turns the engine on that was broken. Now, after the car has been to the shop four times in 19,000 miles, I know that the problem is bigger than that. I replaced the battery twice now under warranty and I really think this car is a lemon. Is there anything I can do about this?

A: The Prius uses the small 12 volt battery to...

The Prius uses the small 12 volt battery to operate the computer and accessories. It uses the big hybrid battery to crank over the engine by turning the electric drive motor. If the 12 volt battery dies, you cannot power up any of the electrical system, since they are all computer controlled. The 12 volt battery may drain if not recharged every couple of days, and may die in 5 to 7 days if the vehicle is not operated. If any accessories are left on, it could kill the battery overnight. A mechanic can check that the excessive parasitic voltage on the battery does not exceed 55 milliamps, if it does, they would have to find the malfunctioning circuit. I recommend contacting YourMechanic to test and verify your system. You should always make sure all interior and exterior lights are off after you lock and walk away from vehicle. Also if your vehicle detects keyless proximity, make sure your keys are far enough away from vehicle after shutdown, and vehicle is locked.

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