Thanks for letting us know of your concerns. I’m quite familiar with the condition you are experiencing on your Rav4. Actually, we’ve even see brand new vehicles from time to time that have a light rust coating on the rotor just like you are describing. Rotors are made from cast iron, so they are susceptible to small rust spots. It’s something that we deal with quite a bit here in the rainy state of Washington :)
This minor rust does not cause any safety or performance issues with your braking system. It will go away after usage and nice weather, but can also recur once wet again. There’s no cause for alarm. I hope that answers your questions. Please feel free to contact me personally if you have any additional concerns.
Rich Conley | Asst.Service Mgr./Customer Relations