Range Indicator

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Pixelpro

Active member
Joined
Nov 27, 2014
Messages
27
I just purchased an i3 Rex and was wondering why the indicator on the dash only shows 68 miles of range on a full charge. It has some miles on it already from test drives. Can this setting be reset?
 
It is cold weather so range will be lower than at other times of the year.

That said, my REx seems to predict 64-68 miles at the moment. But the last time I did a long trip I covered 60 motorway miles (faster always saps the battery) and it was predicting 15 remaining. The lowest I've had it down to for that trip is 8 forecast at the end.

I think the early sales literature was claiming 83 miles and a bit less for the REx so my experience is in the right ball park. The literature also promised 12% increase in range by switching on EcoPro - which doesn't seem to be the case at all!

However, note that I'm not a boy racer and when I say "motorway speeds" I mean 65 most of the time.

One of the good things about having a REx is that you don't need to worry about running out of charge. So experiment and see what you really get out of it.
 
Until we got accustomed to the car we used the REX as a reserve light: drive it to empty a couple of times and you will get an idea of what sort of range YOU will get doing your sort of driving. Don't be surprised if that range creeps up a bit at first as you learn to drive an EV to its best advantage and you get familiar with the various power management strategies.
 
Thanks! I figured it might have also adapted to the driving style of people test driving it. This is why I was wondering if I could do some sort of a reset so I can gauge and practice efficient ev techniques.
 
Pixelpro said:
I figured it might have also adapted to the driving style of people test driving it. This is why I was wondering if I could do some sort of a reset so I can gauge and practice efficient ev techniques.
I doubt that we know the algorithm used to calculate remaining range, but it almost certainly includes previous driving experience. Our former Mitsubishi i-MiEV apparently used the previous 15 miles of driving as one input in its remaining range algorithm. So while there might not be a way to reset the remaining range algorithm, I'm guessing that as distance accumulates, it will use more of your driving style and less of previous driving styles in its remaining range calculation. So it should reflect only your driving style quite soon.

We bought our i3 BEV with 50 miles on the odometer. It was still encased in the white plastic wrapping used during shipping and had not been prepped by the dealer, so those 50 miles were almost certainly just various BMW and dealer employees driving our car on and off the transportation trucks and ships and around the ports of entry (West Coast and Honolulu) and the dealership's lot (i.e., low-speed and probably not very spirited miles). With us having driven 130 Eco Pro+ mostly suburban miles, most of which with active cruise control on and set to 5 mph over the speed limit, in temperatures ranging from the low 70's to the low 80's, after fully charging night before last, the estimated Eco Pro+ range was 108 miles. It's difficult to imagine more ideal EV driving conditions. We drove 82 miles yesterday averaging 5.9 miles/kWh in the same temperatures with 10-20 mph winds at speeds ranging from 35-45 mph on almost flat roads with a few rolling hills and only a little stop-and-go traffic and had 23 miles remaining. So these range estimates likely represent only our driving. The only change I have made it increasing the tire inflation pressures to 51R/43F to try to minimize wheel damage while driving on our pothole-strewn roads. This might have reduced the rolling resistance a bit at the expense of probably slightly less traction due to a smaller tire contact patch area.
 
One of the last selections in hidden menu in the instrument panel is to reset all settings. If u do that it will reset range prediction. Only thing i had to reset afterwards was the clock but still warning you to do this at your own risk.
 
The owner's manual has a very short discussion on this. It will adjust for the current temperature, uses previous history, and adjusts as you drive, plus, if you put in a route, it will also use the elevation data in the nav database to refine the predicted range and prompt you if you can make the trip on the current SOC, and if not, show you charging opportunities along the way. My guess is that it uses a moving average, so eventually, those boy racer spurts you did to show off will no longer be part of the equation. With the pro nav, it shows you your range profile with several concentric circles based on the mode you run. This also takes into account the elevation changes based on what I can see. For example, most things west of me are higher up, and my range going that way is less than going east that gets down to sea level. On a round-trip, it evens out somewhat, but it will do this based on a one-way trip until you enter a route. Many people, myself included, have seen the range display stay constant for 5-10 miles, based on the way you drive (IOW, it doesn't always go down anywhere near linearly depending on how you're driving now and where verses the previous history). Your biggest range hits are high speed and creature comforts (especially if you do not have a heat pump and need heat). Your most reliable predictor is probably the distance/kwhr average readout and the power SOC indication, but that requires doing math in your head. Essentially, the car does this for you based on the range left display, but that can be misleading if you're just getting onto the high-speed roadway, or have to climb a steep grade. Really, it's not much different than the gas gauge on your ICE except there aren't as many fueling stations and your tank isn't as big. After some experience, you'll pretty much know, prior to that, it's a little unnerving if you are going to be pushing the limits.
 
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