Avg. MPG history keeps getting erased!!

[pacifica1]

I have a 2008 Prius (Base model). Everything's been working fine, and then suddenly, all the average MPG history is gone, and does not come back. And I'm getting wild Avg MPG numbers, that are way over the 50 MPG high end... and they can't be true. I pressed the reset button then, to see if that would help bring it back to normal, but it's still erasing all the history. Every time I look at it, only a small column is there and then that goes, too.

Up until this time, I was consistently getting 45-46.5 MPG, and it never went over 46.5. Now it's all over the place. How do I get to where the avg. MPG history will remain? I only pressed the reset button after it all disappeared.

[bwilson4web]

Hummm, I typically keep my mileage using an online database. I just write how many miles were covered on my gasoline receipt(s) and enter the data later when I next get to a computer with internet access:


I've saved over 3 years of data this way.

Bob Wilson

[firepa63]

Once you hit the Reset button, there is no more history. You are starting back at zero and your MPG will change more quickly. On the 04 and 05 Prius, the MPG used to reset with each fuel fill-up. With the 06-09 Prius the MPG doesn't reset (only the miles reset). However, when you hit that reset button, the car is now calculating starting at zero miles and zero gallons.

The best way to keep you MPG history in on a spreadsheet.

[pacifica1]

Right, but I only hit reset after it was all erased, thinking it might go back to normal, but since then, it goes from the upper 50s to low 60s,(which is certainly not accurate) and before it never went beyond 46.7 avg. mpg. Other than keeping my own database on it, can't the car function again, as it did when I bought it last June?

I can't even find how to address this in the owner's manual. I'm wondering if I might have to wait till the next maintenance servicing and have the mechanic look at it. I'm still thinking it might be some simple fix that I just haven't hit upon yet.

[JimN]

Pacifica, I am confused by your description. Do you get an average FE bar every 5 minutes? Does the instantaneous bar on the right constantly fluctuate? Has the total number of miles displayed on the bottom left of the MFD continued to increase since you last pressed the reset button? Does the tank's FE reset when you pump more than a couple of gallons of gas? If the answer is "yes" then your MFD is normal. If the answer is "no" then visit a dealer.