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I do wonder about this firmware update. As far as I know, the physical battery pack condition, and therefore the usable capacity, remains the same after the firmware update. What changes is the measured SOH and the number of bars in the dash, the predicted range on the GOM also increases. But did the actual driving range increase as well?
It's interesting that the Nissan warranty is not measured in % soh but in bars on the dash - and now (roughly) half way through the 8 year warranty on these battery packs the software driving the number of bars is being changed.
To me it looks like Nissan has found a way to reduce the number of warranty claims over the next few years and that is why the recall is being carried out.
Am I missing something?
 

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GOLF GTE PHEV
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To me it looks like Nissan has found a way to reduce the number of warranty claims over the next few years and that is why the recall is being carried out.
Am I missing something?
Honda did a similar thing on their CRZ & other hybrids to fend off warranty claims. They changed the way the SOH is calculated from a % of the original capacity to a % of the actual (i.e. remaining) capacity so 100% was always shown, whereas it could have been 50% in reality. Fraudulent if you ask me.

Nissan haven't done the same, but seem to have just reduced, or removed the buffers at either ends, giving the driver access to more capacity, range and bars on the display.
I wish they'd do the same on the Leaf E+ - be good to have that 'wasted' 6kwh (10%) available.
 

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Nissan Leaf Accenta 30kWh, 3.3kW, 2017
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Mine had a similar increase in in SOH of 78% to 88%, but the real range hasn't really increased, although I haven't really had a decent scientific back-to-back comparison as the weather changed. The GOM went up from around 120-ish to 130-ish, so any real increase would be minor.
 

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I do wonder about this firmware update. As far as I know, the physical battery pack condition, and therefore the usable capacity, remains the same after the firmware update. What changes is the measured SOH and the number of bars in the dash, the predicted range on the GOM also increases. But did the actual driving range increase as well?
It's interesting that the Nissan warranty is not measured in % soh but in bars on the dash - and now (roughly) half way through the 8 year warranty on these battery packs the software driving the number of bars is being changed.
To me it looks like Nissan has found a way to reduce the number of warranty claims over the next few years and that is why the recall is being carried out.
Am I missing something?
The older models had a similar bug, and it was fixed a few years ago. Those cars had the 4A BMS firmware and it was upgraded to 4C. For 2017 MY cars they switched to 6A firmware at the factory, and this update applies to those 6A cars and upgrades them to 6B.

Someone did some testing with the older cars which got the 4A to 4C update. What they found was the BMS on the old firmware would report the battery was empty, but it wasnt. They managed to draw several extra kWh from the pack and the car still didnt actually shut down/turtle mode. Its like theres some sort of cumulative error that builds up that the BMS doesnt correct for, so you end up with an ever larger bottom "buffer". Clearly, if you just ignored the dash showing ---% and kept driving, you could use that bottom buffer up, but no-ones going to take that chance!

The firmware update seems to fix that, and so does infact unlock more capacity. Mine shows more kwh available in leafspy, and my battery SOC is now higher when I arrive at work than it was before the update. Maybe they are fudging the numbers, but in at least my limited experience the usable range has indeed improved by around 10%
 
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