PatsSoxfan

After driving our RX450h for the past week now, I really think that there is something wrong with the "Past Record" graph on the fuel consumption screen. The first couple days, I noticed that the "best fuel average" was never changing. So, I decided to clear everything and start over. This was on July 7 I believe. Well, its seems to have updated the first two days after I reset it (cleared it), but even then the "best fuel average" was this time stuck on 26.6. The average has not at all updated since July 7.

Have any of you that own the 450h had any trouble with this screen?. Or, is there some trick that I am missing? I am going to call the service department at my dealer to ask them about this today. This minor problem aside, the car is everything I was hoping for and then some.

psu77

Patsoxfan,

I have a 2010 Prius which has a similar function. The Past Record graph stores the best mpg you achieved when you cleared the Trip meter. For instance, if right now your average mpg is 27.0 in your trip and you clear it, 27.0 will become your best mpg. If right now your average mpg is 26.0 and you clear it, 26.6 will remain be your Best mpg.

PatsSoxfan

Yes, I realize that when you clear it whatever it is now will continue to show up until the car attains a higher average in the future. And this is the problem. It does not update the daily averages (bars) on the graph. The last update we have is from July 7. Isn't there suppose to be at least one bar per day?

psu77

No, there is a bar for each time you clear the trip odometer.

PatsSoxfan

OK, now I am really confused. So, are you telling me that I need to clear the trip odometer in order for it to work? And then it only shows one bar? That doesn't make sense. What sort of a past record is that? What purpose do the dates on the graph serve then? I know that when we first got the car, there were at least 4 bars showing on the graph.

Please help to further explain this to me. Thanks!

psu77

Pat,

I don't have dates on my version so maybe your system is different. Only advice is then to check the Owners Manual.

PatsSoxfan

I already checked the Owner's Manual and it says it keeps a running record (average) of fuel economy. I am still waiting to hear from the salesman to see if he can shed some light.

psu77

Well I have a RX450h on order so I would like to know how it works too.

rxets

RX350 has daily bar on the graph, and it's updated. I thought 450h has the same stuff!?

I used/reset this feature everytime I filled up the gas tank, so the graph will show all my past 6-7 records.

PatsSoxfan

It does have a daily bar (or it's suppose to) but it is not updating. I talked to the service manager this afternoon and he is trying to find out the scoop. BTW, I thought this consumption graph was exclusive to the RX450h.

rxets

You talked about the stuff on Navi Owner Manual PAGE 156/157, right? Yes, we do have them. And, my graphic bars in Past Records are updating.


Lexus cannot make 350 too far behind 450h...

tsmith167

I am having same issue. Cleared data on nav screen about 5 or 6 days ago and I have two bars. I have reset the trip mpg on the steering wheel once. This may be why I only have two bars but this does not seem to be the way it should work. Seems to me the bar graph should show your daily mpg's. ( Therefore, I would have 5 or 6 bars)

rxets

In Ave MPG screen on the panel, if you press the "reset", this will add the new bar into the graph on Navi (past records). If you press twice, 2 more bars will be added.

PatsSoxfan

Are you sure about this? Granted that I have not tried your suggestion yet (my wife has the car and I am at work), but does that make much sense? So let me see if I understand this. If one presses the "enter/reset" button on the steering wheel to reset the average mpg shown on the instrument panel, that will then pop up a bar on the "past record" screen showing what the average mpg was was prior to your resetting it. Is that right? Then, if I press the reset button on the steering wheel again a few seconds later, another bar will show up on the "past record" screen. Now, what good does that do? I suppose I can see some use for this approach if you press the reset button once in a while so that it does give you a track record of what the fuel consumption has been over the past week or so. What about the "best mpg" on the "past record" screen? Where does that come from? Is that a determination of what your best mpg was for the various times you pressed the reset button?

Finally, where is all this explained on the Owner's Manual? I looked at it many times and nowhere did I see this sort of explanation. The salesman and the service manager at my dealer also had no clue of how this works. Until I read your post, I really thought that there is some sort of a software mistake for the past record screen. And I am still not convinced (until I test your explanation later today) that there is not a software problem. I hope your are right. Thanks very much for being a great source of information on this forum, rxets.

rxets

I walked away to my company's parking lot to demo all of these, and want to make sure I answer you correctly based on what I've found from my RX350 Navi.

* I also attached the consumption screen shot. It's updating.


Yes. this is correct and is what happens on my RX. The past Record can only display 6 bars, including the current real-time one.



I tried this when my car wasn't moving. It wouldn't work. I had to drive forward for a few feet, which made my average MPG updated. Then I can reset it again, another bar will be displayed and all the old bars will be moved to the left.



I don't know how other ppl do, but I used this feature to record all the history of my driving MPG between each fill-up in the gas station. I can clearly compare what I have been driving in the past 5 periods of time.

As for best mpg, this indicates the best MPG of the certain "time" from your Past Record. Remember, it's from your whole past record history, not just the 6 bars on your screen. However, I coulnd't determine the length/details of "time". For example, I had a few 28/29 MPG bars last week, but my best MPG only showed 27.6.

If you click "clear" button, it'll be reset to 0. You can see the pics below.



It's on Navi Owner Manual Page 156. It's hard for us to fully understand what Lexus/Toyota are thinking of. They may create the system based on the understanding/theories/methods by portions of ppl from JDM or the whole world. It's uneasy to find all the car manufactors using the same thoughts to create their systems. What we only can do is find the car we like and we trust, then enjoy it.



Btw, no problem. Don't have to mention that. Just want to share info.