He he. Now you succinctly summed up the problem philosophy has been grappling with for the last 250 years. The problem is that we are changing reality by watching it. We are loading it in a way to suit our needs. My reality isn't the same as yours. Neither of us has access to the real reality. So much philosophers can agree on. No philosopher since Plato has claimed that the true reality is accessible to any human ever. So I think that a good answer is that neither you nor I know that correct interpretation of the colour of the car.
But that doesn't mean that there is no reality. Philosophical relativism is not the same thing as reality being arbitrary. Reality is there, we just can't use our common sense or senses and pretend like that's some kind of definite proof of anything. This is where semantics and science helps. Numbers and measurements are less open to interpretations than vague concepts like colour or feelings.
My car is R: 256, G: 0, B: 0
Of course blind faith is wrong. Blind faith is the same thing as arbitrary faith. It's just a rhetoric question. Blind faith is always worthless. Nobody believes anything based on blind faith. It's always based on evidence and conclusions drawn from them. Always. One might be wrong or basing ones faith on sketchy evidence, but that's not the same thing as blind faith.
I believe I answered this in my first post in this thread.