When driving a used car, it's not uncommon for your battery to be "dead." And this is where many modern car owners can be in for a surprise. The traditional key has been replaced by key fobs with buttons, and not every owner knows that this piece of plastic hides the metal "blade" of the key, which opens the driver's door and accesses the hood. But a surprise can also await you under the hood: many car manufacturers hide the battery either in the cabin (yes, it happens!) or in the trunk. To avoid such situations, carefully read your car's owner's manual, which always describes such situations in detail.