Code MCU_u006 was reported by the “Centre display (MCU)” controller in the car. The letter “u” in the middle places it among entries of the user action required type.
The Media Control Unit — the computer behind the centre screen. Besides its own faults, everyday driver notices come from here too: empty washer fluid, an open door, a flat key fob battery. Most MCU codes are therefore not a vehicle defect.
Not a defect. The car is waiting for you — press the brake, close a door, top up a fluid, change a setting.
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 media control unit (MCU) has detected that the driver door is open.
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.