I recently took my 2004 Prius in for an inspection and was surprised when the dealship mentioned I had a defective battery (front battery not the regenerating one underneath the car). It took about a week to get a new battery from Toyota (obviously under warrenty). I was surprised because the car didn't experience any signs beforehand of a low battery (e.g. light indicator, etc.). I'd like to hear if other owners have experienced any similiar circumstances.