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Discussion Starter · #1 ·
I’m not a very consistent driver.
either I’m the Greenpeace side of the fence, or on the AMG side.

so it bothers me that the range meter shows 200kms when I’m driving slow…. Because it was influenced by that faster commute the day before.

is There any way to “fix” this? (Apart from driving slowly for 6 months so the range estimation forgets that it has 408hp always available to propel the vehicle forward like a rocket?)

:)

Any hints are appreciated :)
 

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I understand setting a destination in sat nav with Electric Intelligence enabled (and a dynamic mode selected?) will help the computer give more accurate advice.

I don't know how to reset to WLTP (maybe try create a new user profile?) so I sometimes calculate myself using a formula -

range = (battery percentage) x 80 / (efficiency in kwh per 100km)

For EQA replace 80 with 71 as EQA is smaller battery kwh capacity.

So if I expect to get 24 kwh per 100km on motorway and battery is 77% then range is

77 x 80 / 24 = 256km range

Or on autobahn and I expect 40kwh per 100km then 77% range is

77 x 80 / 40 = 154km range

Or assuming car is achieving WLTP 373km range is

77 x 80 / 21 = 293km range

Or assuming car is achieving WLTP 417km range is

77 x 80 / 19 = 324km range

Or assuming car is achieving WLTP 432km range is

77 x 80 / 18 = 342km range

Or if battery is a low 20% then WLTP 417km range is

20 x 80 / 19 = 84km range


You can find out what efficiency the car uses for it's own range calculation formula by this slightly different formula-

(efficiency in kw per 100km) = (battery percentage) x 80 / (range meter)

So if range meter predicts 220km range and battery is 70% then the car thinks that efficiency will be

70 x 80 / 220 = 25km per 100km


 

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I think you know all these formulas already and would prefer car to show but a third, even simpler, formula you can use to "correct" range to WLTP is:

WLTP * Battery percentage / 100

So if you expect WLTP to be 417km and you see battery is at 44% then the WLTP range left is:

417 * 44 / 100 = 183km

There might be a ODB scanner device that calculates this automatically which I can check for if interested in that too.
 

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I’m not a very consistent driver.
either I’m the Greenpeace side of the fence, or on the AMG side.

so it bothers me that the range meter shows 200kms when I’m driving slow…. Because it was influenced by that faster commute the day before.

is There any way to “fix” this? (Apart from driving slowly for 6 months so the range estimation forgets that it has 408hp always available to propel the vehicle forward like a rocket?)

:)

Any hints are appreciated :)
After driving an EV for some time you get used to mostly ignoring the range meters, other than out of curiosity. The problem is as you said, they are always based on past performance, the only thing they tell you is how far you can get if you repeat the past circumstances.
There are so many things that affect the range of the car, you need to work out an approximate distance you can cover per battery percentage with regard to your different driving styles, temperature, gradients, etc, then multiply that by the battery percentage display. Same as you would have used a fuel gauge in a petrol engine car (if one bar on the gauge equals 10 litres and you know you can get 16km/litre, you can work out your range accordingly) before range displays became available.
I have always thought the mental arithmetic would be easier if EV cars showed how many kWh were in the battery instead of percentage. Rather than you having to read one display showing what miles/kWh or kWh/ 100km you are getting then working out what kWh is in X percent battery, then doing the multiplication to see how far you can get.
My car readings are in Imperial so I multiply my battery percentage by 2.7 to get the range in miles (4.3 would give an answer in Km). This gives an approximation for me in good conditions and I can adapt it to take account of variables.
 

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(efficiency in kw per 100km) = (battery percentage) x 80 / (range meter)

So if range meter predicts 220km range and battery is 70% then the car thinks that efficiency will be
70 x 80 / 220 = 25km per 100km
70 x 80 / 220 = 25kwh per 100km

Nicely simplified, FDR
 
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