BTX4: the 90 kWh pack

Tesla updates its record when it replaces a pack, but a replacement done outside Tesla may not show, so ask about any battery work in the car's history. The pack code is the pack on Tesla's record for this car, usually the one it was built with: Tesla can update it after a replacement, and one done outside Tesla may not show. It does not change with software, and it is not always the badge on the trunk.

Older Model S and Model X pack codes carry the nominal capacity in their digits: BT40, BT60, BT70 and BT85. The 75, 90 and 100 kWh packs are recorded as BTX5 or BTX7, BTX4 and BTX6, and the report reads both forms. Two things the code does not tell you. First, the badge on the trunk is not always the pack: Tesla sold some cars as a smaller size than the pack inside, limited in software, and its record shows that in Tesla's trim code (a 60 on a 75 kWh pack, for example), not in the pack code, so the report says a pack was limited only when that trim code says so. Second, the pack code is the pack on Tesla's record for the car, usually the one it was built with: Tesla can update it after a replacement, and one done outside Tesla may not show. From 2019 the codes change form, BT37 and its successors, and the digits no longer encode capacity. For those the report uses the public option-code lists where they all agree, so BT37 is 75 kWh with Panasonic cells and BT42 is 82 kWh with Panasonic cells, and prints the code alone where they do not.

The free decoder reads the Full Self-Driving codes from the factory record for any VIN. The Supercharging code and every other one are in the $1.99 report.

See a sample report →