Code BC_w002 was reported by the “Body controller” controller in the car. The letter “w” in the middle places it among entries of the warning type.
The controller for exterior lighting and signalling. These codes mostly cover turn indicator failures.
The car is flagging that something is not right. Driving is usually still possible, but some function may be limited.
This is how the fault is named inside the car's firmware. For codes without a description it is the most precise clue there is — the name itself says what the event is about.
The text below comes from Tesla's technical documentation. We leave it in the original English so that translation cannot shift its meaning.
The right indicator is not functioning as expected and may be flashing faster than normal.
If a fault (open, short, over-current..etc) is detected on any of the driven lamp outputs required for signaling (which will be different for each vehicle region), then the frequency of the flashing signal sent by the BCM to the turn signals is intentionally doubled in speed to indicate an issue.
The vehicle can only determine if the issue is for the left or right indicator. It cannot determine if the issue is in the front or rear indicator, so they both must be checked.
Copy it exactly, letter and number included. Photographing the screen is safest — codes often differ by a single digit, and mixing them up leads somewhere else entirely.
Some codes clear after a screen restart or after the car sits locked for a few hours. If the code does not come back, it was usually a one-off glitch.
A one-off entry and a code that appears after every drive are two different things. It helps a service centre enormously if you know exactly when it shows up.
With airbags, brakes, steering and high voltage there is no point waiting it out. With the other groups you can watch and see whether the code returns at all.
Error codes are only part of the picture. For cars on TesList you also see battery health pulled straight from the vehicle, plus a price calculator that works out from current listings what a given car is actually worth today.