JavaScript foundation - prototypes : challenge 1

Hi, Just a bit stumped here as to what I need to do to make this first part work. I thought I assigned the Car constructor 'model' to the carPrototype argument model correctly, but I'm just not getting it, nor is it giving me a valid hint (Always says "Bummer! The Car doesn't have the 'model' set correctly" no matter what I do with the code, including deleting the entire code) . What am I missing?

var carPrototype = { model: "generic", currentGear: 0, increaseGear: function() { this.currentGear ++; }, decreaseGear: function() { this.currentGear--; } }

  function Car() {
    this.model = model;
  }