waikalua said:
Since battery capacity is a MAJOR factor in the resale value of an EV, how is this different from odometer tampering?
Re-programming the BMS has the unintended consequence of resetting capacity bars and other parameters. This will be temporary, probably settle down after a month. Expect to lose a bar or two again.
Odometer tampering is deceptive, intentional and permanent. This isn't permanent. Nissan's goal is not to disguise true battery degradation and it will settle down within a reasonably short period of time.
EV's (and modern cars in general) are like computers on wheels. When you call tech support one of the early troubleshooting steps will be to upgrade firmware to a current revision, it sets a baseline for troubleshooting. If that doesn't help then additional actions will be taken. This is no different, Nisan need to get your firmware to a current and known state and can act accordingly thereafter.
It can be frustrating to see what apears to be a valid warranty claim evaporate, but another month and you will know the true state of your battery and warranty eligibility.