dgpcolorado said:
...The GOM can't know whether you plan to go uphill or downhill, how fast you plan to drive in the future...
I guess my point is that the GOM is actually worse than you describe. As best I can tell the displayed range is roughly:
At startup in ECO:
GOM=(Capacity-2 kWh)*6mi/kWh
At startup in D:
GOM=(Capacity-2 kWh)*5.4mi/kWh
After 15-20 miles in D if you are getting 4 mi/kWh:
GOM=(Capacity-2 kWh)*4mi/kWh
After 15-20 miles in ECO if you are getting 4 mi/kWh over the last few miles:
GOM=(Capacity-2 kWh)*1.1*4mi/kWh
After a couple hundred feet elevation on a 6% grade hill:
At startup in D:
GOM=(Capacity-2 kWh)*2.5mi/kWh
I can understand keeping the reserve, however by choosing an eye popping initial efficiency estimate instead of consistently using recent history you end up with these persistent freakouts over the range dropping 5 miles by time you get a mile down the road. Nothing will help the mountain dwellers, but plenty of near flatlanders end up rather shocked when they cannot come even close to the displayed hundred odd miles despite only doing modest city driving with just a little freeway. I am convinced that the way Nissan handled the GOM really amplifies range anxiety rather unnecessarily. Folks end up having their new cars towed halfway home with over half a charge because they saw the GOM go from 110 to 27 and assume they used 75% of their battery when they likely used under half, really rather sad.
The things that really stick in my craw is the start up number which appears to be slightly influenced by recent driving, but mostly by the outside air temperature, or maybe a magic 8-ball. Given all the downloaded data to Nissan they should easily be able to use a number from the last ~100 miles of your actual driving as the initial estimate, but they instead start with a wildly optimistic number instead. I am pretty darn sure this is to help move vehicles off the lot more than anything else. Next, the ECO mode efficiency used to calculate a number appears to never quite converge on your actual efficiency, instead it appears that as they keep the original +10% range expectation above what your recent ECO driving actually indicates. The Carwings website chronically displays very different efficiencies than the dash as well, which after 4 years really baffles me (perhaps they farmed out the code and nobody there knows how to maintain it?).
Basically the instrument cluster has had ever last number or piece of data run through a cartoon filter before being displayed. The speedometer is chronically high, the capacity bars are grossly inequal despite equal appearance, whatever the heck the trees are supposed to mean, etc. It is a great little car, but some of the missteps around the instrument cluster, the 2011/2012 heater control, and the lackluster navigation system really baffle me compared to the rest of the execution.