Sorry if this has been answered, I cannot find it on the forum. I had the truck's radio on while waxing yesterday. When I drove this morning I noticed that the 30 minute fuel history bars were gone and both trip mpg numbers had decreased. All evidence points to indicated mileage being reduced as if the truck was getting 0 mpg for some period of time. Has anyone experience this? The manual states fuel history is "based on driving". I thought I would ask before I try to replicate.

 

Interesting.
If I base the graph on minutes, which it is, I guess I can see why the entire gauge is blank. For the past 30 minutes there is no history to report. I would think the system is smart enough to know better.
The real test is if your trip meter would indicate something like 8 mpg instead of whatever you had before. It sounds like you said that happened though, right? Your average MPG on the trip screen is greatly reduced?
If I took a crappy hit like that for a period of time, my overall would be about 8 mpg, not 15.

I've had accessory on before while making FORScan changes but never like what you have said, leaving accessory active for the long period of time, I therefore cannot confirm the MPG and/or history was affected. It's been a long long time that my accessory mode has been active for longer than a minute.

 

Yes, when the vehicle is running the clock is running, so your mileage bars will show nothing.

However, I don't think that happens if you just turn on the radio by pushing the button. Sounds like you turned on accessories or started the truck?

 

The accessories were left on as I lowered the window. Update: could not duplicate; senility seems to be setting in, thank you for the comments-

 

Simply push radio button. Or not, the system really drains the battery - it's not just a radio.

 

Sorry, could not duplicate the mileage discrepancy in my original post. Thanks Rick-