Driving range display 'changes' after NTB11038 Svc Campaign

[ttweed]

We have only put 500 miles on our car so far, charging only on L1 to 80% each night since the Blink unit is not yet functional (waiting on inspection now, and then the 2nd meter set), and have only experienced one low battery warning. It came at 19 miles estimated range. We have the "B" firmware and are going in this morning for the service to "upgrade" the software. It will be interesting to see what changes that makes.

TT

 

[Gonewild]

Well I hope I did not screw myself by getting the update even though I was not having any issues. I was off yesterday and decided to call the dealer. The dealer said he has programed 4 car so far? I will be going to work in a few hours and I should have used 5 bars and on my way home I used 4 bars and should have mid 20's on miles left after my 76 mile highway trip.

 

[Fabio]

The range display is trying to achieve an impossible task: predict the future.

At any given time, the car has 2 pieces of info: the SOC and how much power you have been using.
I have been reading how everyone here seems to be smarter than Nissan's engineers and how the algorithm should have been done, but the basic problem it tries to solve can not be solved, as there is no way to know how much power per mile the driver will be using in the future.

I'll also note that I believe (haven't yet proven) that the range is indeed more accurate. I view this as a good thing.

 

[Jimmydreams]

My take on the 'new and improved' range indicators....

The bars seem to be pretty much as they were, at least for my drive in to work. The miles remaining seemed to drop faster when going up hills, and climb faster when going down hills. Maybe that's just my opinion....but it did seem to hold a higher number longer (ie. it dropped quickly from 105 (in ECO) to around 90 and seemed to hang around 90 even though I went 7-10 miles.)

We shall see what the pack shows when I pull in the driveway. But after my commute TO work, the miles remaining seems 3-4 miles lower than normal, and the Carwings is showing 50% charge when it ROUTINELY showed 58% charge. So it looks like they've made the bars a bit more coservative (possibly giving more indicated range at the very end???)

???

 

[turbo2ltr]

Just some random tidbits..

Range at the low battery warnings and turtle are completely dependent on the type of driving you are doing. But they always happen at the same SOC.

Personally, after 2500 miles, I've noticed that the battery seems to be increasing capacity, at least when it comes to bars. I can now (sometimes) make it to work, after doing 70 on the highway, and only lose one bar from a 100% charge, whereas before I'd always lose two bars.

So this morning I plugged in my software and found that the SOC value after a 100% charge has "drifted" up since the last time I recorded CAN data a month and a half ago. Meaning what I see is not SOC but capacity. (SOC should always be 100% after completing a charge profile...at least that's the way we've always done it).

Anyone else experience the battery "breaking in"?


Gonewild, got a laptop you can put in the car on your trip? I'll set you up to collect some data.

 

[GeekEV]

Correction to my earlier comments. I did find some notes from my first low battery scenario and I got it at 18 miles, as others have commented (very low was at 11, and turtle was 3 miles later) . Now low battery occurs at 8 (twice, post update). I may have to push it lower just to see where the other thresholds are now.

 

[garygid]

Low Battery warning at 17 real miles gives one a CHANCE of locating an e-station.

A "first" warning at just 7 or 8 real miles remaining is usually way TOO LATE to reach an e-station.

In any case, it looks like those who have gotten to know what the lower SOC bars and Remaining Miles estimates mean on their car ... will need to re-calibrate their thinking after this "Upgrade".

 

[Gonewild]

Wow, I just checked my Carwings to see if it is charged and ready for my drive to work today. And normally I have 109 to 124 or so mile starting range but today I have only 81 miles that should make the 76 miles RT to work. But that must be do to the software change.

 

[EVDRIVER]

It is not important where the low battery indicator comes on it is more important as to how they calculate that 8 miles. If it based on you last going down hill you could be in trouble, better if last going up a huge grade. Perhaps it is calculated to give you 8 miles at you worst trip economy to be conservative which is far better. People are confusing SOC and miles at times. I'm not sure how many times it will become evident that SOC is far more valuable info in addition to any other data Nissan provides. If one knows SOC accurately then they can make safe decisions on range at the bottom of the scale. Dummy lights and bars still don't provide accurate info.

 

[DarkStar]

Wow, I just checked my Carwings to see if it is charged and ready for my drive to work today. And normally I have 109 to 124 or so mile starting range but today I have only 81 miles that should make the 76 miles RT to work. But that must be do to the software change.

I noticed the exact same thing this morning. My RT is 56 miles though so I'm in good shape. When I hopped in the car and put it in ECO mode though the dashboard displayed 110 miles, still lower than the usual 120 miles I saw pre-update.

 

[EVDRIVER]

Wow, I just checked my Carwings to see if it is charged and ready for my drive to work today. And normally I have 109 to 124 or so mile starting range but today I have only 81 miles that should make the 76 miles RT to work. But that must be do to the software change.

I noticed the exact same thing this morning. My RT is 56 miles though so I'm in good shape. When I hopped in the car and put it in ECO mode though the dashboard displayed 110 miles, still lower than the usual 120 miles I saw pre-update.

So you can drive 109-124 miles if you go to empty? My guess is No. Sounds like it may be taking a better average. I noticed the dash display of instant economy is far from instant, holding 8kw per mile while climbing a hill for a long time! Never saw that stuck before.

 

[evnow]

So you can drive 109-124 miles if you go to empty? My guess is No. Sounds like it may be taking a better average.

Right.

The problem is - when we come home or to work, the last few miles are usually in low speed/heavy traffic areas. That means last few miles are at high efficiency. If the range calculation is based on this, it would be too optimistic.

They need to discount the last few miles of low speed driving but consider last few miles of high speed driving.

 

[IBELEAF]

Just performed update as well, visit took 15 minutes as I opted out of car wash. I can't recall but I either lost 1 or 2 bars, hopefully will make it home now

 

[Gonewild]

No I do not get that high of mileage because I drive on the freeway at 62mph. I am at work not and I have the same SOC and normal 67 miles left. I just drove 38 miles of my 76 RT. I will report only a slow display change if any change at all. So far I am happy with the update as all is well. I never had the AC problem but I did not use it on charger since the notice came out to be safe.

 

[Gonewild]

I just remembered my timer was turned off after the update. The time and % was still set I just had to push the timer 1 and 2 buttons again.

 

[TEG]

So you can drive 109-124 miles if you go to empty? My guess is No. Sounds like it may be taking a better average.

Right.

The problem is - when we come home or to work, the last few miles are usually in low speed/heavy traffic areas. That means last few miles are at high efficiency. If the range calculation is based on this, it would be too optimistic.

They need to discount the last few miles of low speed driving but consider last few miles of high speed driving.

+1

Like many, I have 90% highway commute, followed by 10% slow through town once I get off the highway.
Estimated range calculations ought to take into account the wh/mi of the whole trip, not just very recent data.

 

[LTLFTcomposite]

The range display is trying to achieve an impossible task: predict the future.

At any given time, the car has 2 pieces of info: the SOC and how much power you have been using.
I have been reading how everyone here seems to be smarter than Nissan's engineers and how the algorithm should have been done, but the basic problem it tries to solve can not be solved, as there is no way to know how much power per mile the driver will be using in the future.

Would it be better instead of giving a single number that says "You have X miles left" to give a range:

|--------------------------------|
12----------^30-----------------52

Three numbers: worst case, best case, and average expectation based on your normal history

 

[Long4Leaf]

Would it be better instead of giving a single number that says "You have X miles left" to give a range:

|--------------------------------|
12----------^30-----------------52

Three numbers: worst case, best case, and average expectation based on your normal history

I was thinking something similar. Allow the display to be toggled between "last mile average", "last 5 mile average", "last 10 mile average", "average since you reset your mi/kWhr".

Something like that. Then it allows me to estimate when driving conditions change but are expected to be that way for a while AND when driving conditions change but is expected to be temporary/averaged out.

 

[evnow]

Just performed update as well, visit took 15 minutes as I opted out of car wash. I can't recall but I either lost 1 or 2 bars, hopefully will make it home now

Where did you get it done ?

 

[GeekEV]

Would it be better instead of giving a single number that says "You have X miles left" to give a range:
<snip>
Three numbers: worst case, best case, and average expectation based on your normal history

I really like that idea. Even better if you plot it on a graph that runs the full 0 - 100 mile "expected" range to give a quick visual reference of how you're doing. Something like this:

0 (========================================) 100
       |------^-------|
      12      30      52

0 (========================================) 100
          |---^----|
         20   30   40

Not only would it give you a good feeling for how much you have left, it would also give you a feeling for how "certain" the car is about its estimates... Very useful info!