Hi; I just got a '17 C-Max hybrid. I traded in a Fusion hybrid - which I got shortly after I found out that Ford 'got' the transmission from Toyota. I got the C-Max shortly after finding out it not only comes as a hybrid, but that it's the same drivetrain as my Fusion (which I liked for 120K). The C-Max is a CPO w/ 100K drivetrain warr. I put gas in the C-Max, and the fuel gauge changed from white (before fill up) to yellow. This isn't in the manual (with quite a few other things). What does it mean? Are there other colors? What to they mean?!?