another low range on full charge question

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Anonymous

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So, I've read several of the posts here regarding low range readings on GOM following full charging.
I'm having similar results lately in winter conditions; with about 6500 miles total thus far, I've been normally getting 235-240++ mile
range showing on GOM thru summer / fall until the last month. [Bought in May]
I live in No. Calif. w/ mild winter temps [mid 50's to low 60's daytime / mid to low 40's night] [ summer temps very similar & only
around 5 degrees higher]
In only the last month I've been using the heater liberally.... like 77*, yes I LIKE it HOT! [yeah, I know use heated seats / s. wheel instead],
Efficiency readings have gone from 4.1 mi./kw to about 3.1mi/km. I'm now getting 165-180 on the main range GOM w/ full charge. So, I read here that the lower #'s are due to past energy usage [in this case it has to be the heater as I'm driving
the same route and very much the same style]
I realize that I've been lazy & only have read selected parts of the owners manual, & I'm sure it's probably mentioned
in there somewhere, but is there a way to clear the prior parameters before charging to 'start over' w/ a clean slate on the est. range?
[ Unfortunately I took the manual out of the car for 'evening reading' & currently can't find where I've left it...! ] There is a LOT of info.
there.
I had a Leaf prior to the Bolt, & I remember how bad that GOM was....somehow I had thought the Bolt was different in that
when you FULLY charged it, it would AUTO RESET itself to show the actual mileage based on the full battery w/ an idealized efficiency
of 4 miles per kwh [thus the advertised 240 miles from a 60kwh battery pack].
Anyway, I assume that if my GOM range shows 165 miles on a full charge after using the heater from prior driving, & I THEN drive
w/ out the heater [as I've done in the summer to get a 240 mile GOM range], that of course it will at some point again achieve the
240 mile range on the dash. [i.e; the algorithm for GOM will reset w/ new drive cycle]
Of course this must be the case; then the GOM would adjust to my lower energy usage, again showing my usual
higher range since the battery has been charged full & I'm using less energy......as after all, there is the full 60Kwh of energy stored in batt.
& if it shows on the 'energy' screen that I'm driving w/ at least a 4 mile per kwh efficiency, I'll still go about the 240 miles, regardless of
what the GOM indicates.
If this were to be the case then GOM range indicator should adjust gradually by lowering, say 4 miles less per every 10 miles traveled.
[i.e., about 40 miles more per 100 miles / 80 more per 200 miles] This would be the difference between the prior 245 mile range and
the new 165 mile range, which is 80 miles. I realize I don't actually remember what the top 'best' est. GOM range is since I just never
pay attention to that one...if I did I'm guessing that it's prob. over 200 miles when the main average one is showing 165 miles, as it's
trying to 'best case' by adjusting for lower energy use [in this case no heater.]
Wondering if the adjustment back to the high mileage est. on the center range gauge would happen in just 1 drive cycle, & would
probably have to drive the full 200+ miles in one shot....? Point here is that I don't understand at what point the 'prior' drive cycle
stored energy usage stops diluting the 'new' driving energy efficiency & thus the range GOM.
 
Boltnit said:
I had a Leaf prior to the Bolt, & I remember how bad that GOM was....somehow I had thought the Bolt was different in that
when you FULLY charged it, it would AUTO RESET itself to show the actual mileage based on the full battery w/ an idealized efficiency
of 4 miles per kwh [thus the advertised 240 miles from a 60kwh battery pack].

Auto reset to an idealized efficiency would be a bad GOM.

The reasons why a GOM is not accurate include:

  • 1) The GOM doesn't know where you are going to drive. It might, if you enter a trip into a nav system linked to the car. Or even predict based on location, time of day, day of week and the vacation schedule in your phone.
    2) The GOM doesn't know how you are going to drive. Burning rubber to 85 MPH, or hypermiling? Traffic jam or open road?
    3) The GOM doesn't know the temperature of the battery. It could easily, of course, but idealized efficiency is at one battery temperature.
    4) The GOM doesn't know the weather outside. Wind, rain, snow, temperature, and so on.

Some of this can be guessed at by looking at past history over multiple drive/charge cycles. Which is why it is a Guess O Meter. Low efficiency might mean that the weather outside is winter. By removing the past history, the guess wouldn't be as good.

The manual is online, and can easily be found with a search engine.
 
Just reset your trip meter.
You can do this any time.

Know in your head you have 59.5 kWh on a full charge in above 70 degree weather.

Probably 59.0 kWh on a full charge in 60 degree.
Probably 58.0 kWh in 50 degree weather.
Probably 56.5 kWh in 40 degree weather.

In your head (or use a calculator)....

IF you drive at 4 mi/kWh you’ll go:
4 x 58 = 232 miles at 50 degrees.

IF you drive at 3.1 mi/kWh you’ll go:
3.1 x 56.5 = 175 miles at 40 degrees.
 
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