tracking lifetime on Trip B

You reset ODO?

 

I think he means the MPG for the ODO has been reset.

 

They make it WAY too easy to reset the ODO MPG!!! I've done it twice. The first time was on purpose when I bought the car. The second time was not on purpose.

But on the good side, after you drive another 20-30k miles, it shouldn't make much difference. Mine now reads about what it did before I accidentally left my thumb on the button too long.

 

YES; used car dealerships do it all the time. LoL; always get a CarFax for comparison.

Yep, Trip A for physical tank to tank mpg calculations, and Trip B for oil changes.

FWIW; they also reset when I corrected the wrong date the dealership inputted into my system. Not the trip counters, but the long term onboard calculations.

 

I do the same thing. I keep the TripB as my backup for the lifetime MPG in case I accidentally reset the mpg data attached to the ODO. What is funny about my Trip B is that it actually shows slightly longer miles than ODO does. It was that way from the day when I bought the car with 8 miles on the ODO. How is that possible?

Does the lifetime MPG data get reset if the 12v battery is disconnected? I've read it does, but I have not replaced the 12v battery on my PP yet, so I don't know for sure.

 

Was wondering the same.

For OP: start a spreadsheet; bullet-proof, and more accurate; the car tends to “cook the books” on mpg. On 3rd gen to the tune of 7~8% optimistic.

 

For our 2014 Pathfinder Hybrid, the trip info including the Tripmeter A and B were reset, but the eco data which includes the lifetime MPG did not get reset. It must have a backup battery for the computer memory or the data must be kept on a non-volatile rewritable memory chip.

 

LoL, It only took 3 months to figure out the dealer inputted the wrong date into my system. Off by a day; which left me scratching my head once or twice a week - when my scheduled charging was off........ Thought the car was haunted

 

Nope. I've disconnected my 12V a few times and also replace the 12V on my wife's '17 Prius. All MPG data remained. Radio presets were also unaffected. Just lost the clock and calendar settings.

 

Thanks. How about The ECO diary and DRIVE MONITOR and DRIVE MONITOR 2 data? They also contain cumulative data that I track. If they don't get reset by removing the 12v battery, then I can play with detaching the 12v battery without fear of losing the data I track. Clock and calendar setting is easy to fix and does not affect much. I suppose, if the calendar data get reset, then any charge schedule would also have to be re-entered?

 

Is anything the 4th gen car tells you still "cooked" by about 7~8% (on the optimistic side, of course...)? That's the case with 3rd gen.

 

Yep, for my 2017 PP, the displayed MPG was 6.02% optimistic compared to the hand calculated full-tank method in 83 fill-ups. For my 2020 PP, it was +7.96% in 7 fill-ups. And for my current 2021 PP, it is +8.69% in 5 fill-ups.

 

That stayed. It only holds so much data, though, so the old stuff eventually gets pushed out by the new.

Yes, but not that much. Here are calculated vs indicated MPG for the two road trips I've had in the Prime. Calculated is in the left column and indicated in the right. I forgot to record a couple of the indicated MPG readings on the first trip. As you can see, the error varied from tank to tank.

 

Maybe not so much the “error” variations, as pumping vagaries. I suspect if you could eliminate the latter the former would be very consistent.

 

Yes, I know only 1 year of monthly (3 screens) and 32 days of daily (8 screens) Eco Diary records are available, and older ones get purged. But that duration is usually long enough to transcribe the data into my separate spreadsheet. If they disappear at the time of 12v battery disconnection, I would first have to make sure to copy all the data up to date, But it sounds that is not necessary. As for the DM and DM2, I also keep record of both in a spreadsheet. DM has the lifetime record of EV ratio which is important if I need to figure out actual engine use. And DM2 has the lifetime EV efficiency data which is more important for me to keep than the lifetime mpg.

 

You can read this thread: What is your DTE after fill-up? | PriusChat

The DTE is closely related to the last tank full of HV-only MPG. It has nothing to do with the EV Mode portion of the drive, so it is not the MPG displayed on the dash, but actual gas used during HV mode only. If your driving condition is very consistent, then it does not change much from tank to tank. But in my case, if my HV mode drives are different such as mostly commuting at 35mph or a single drive of 500+miles on a highway at 75mph, or environmental condition changes such as getting very cold or hot, then I notice a fairly good amount of changes from tank to tank. My DTE has ranged from a low of 450 to a high of 574 after a fill-up.