I have had my 08 Prius for 6 months and most of the time when I start the Prius with the Power button (with my foot on the brake), the light on the Power Button turns geen then goes out. This has been normal for the last 6 months. Now when I start the Prius with the Power Button and by foot on the brake, the light on the Power Button turns Amber and then goes out. The dash shows READY in both cases, but now my MPG seems to have gone down by 20%. Any ideas on why the Power Button ligh is Green or Amber when starting the Prius?
My 04 has a little amber LED on the power button , it lights briefly when I turn on the car. Driving the car tonight, I was reminded it glows green with the lights on. Does it make a difference if you turn on your lights, the green is not at the same spot for the amber LED, it's a back highlight for the power button. Wonder if little night driving in the summer is a factor here for your question. For what it's worth I doubt your lower gas mileage is connected to your power button.
