As has been inferred before about Tesla's OTA updates with regard to its limitations, here's an example were a processor change
was necessitated for the AP function and an OTA update, e.g. a firmware solution, wasn't possible. And this is a propriety Tesla
ECU, i.e. the AP function. So when ECUs are sourced from outside vendors, e.g. ABS/stability control, OTA updates become even
more difficult to nearly impossible. As indicated, OTA updates are available for the older AP system, but that system would not have
all the capabilities of the later system design, i.e. a newer processor and possible newer system features.
https://www.teslarati.com/elon-musk-tes ... -retrofit/
In a recent tweet, Elon Musk confirmed that Tesla Model S and Model X owners whose vehicles are equipped with older Media Control Units could be retrofitted with the company’s new x86_64-based MCU.
Most all Tesla OTA updates are to the MCU and/or the AP functions;https://www.teslarati.com/category/model-s/firmware/
An interesting Tesla forum discussion from 2014:https://forums.tesla.com/de_AT/forum/fo ... difference
Leaf SL MY 9/13: 65K miles, 50 Ahrs, 5.2 miles/kWh (average), L2 charges to 100% > 1000, max battery temp < 95F, min discharge point > 20 Ahrs