Code TAS2_a222 was reported by the “Air suspension — newer control board” controller in the car. The letter “a” in the middle places it among entries of the alert type.
The newer air suspension control board. The codes mean the same as the TAS group, and the descriptions tend to be more detailed — including how often each check runs.
The most common type. The car logged the event and may have shown it on the screen. The range is wide — from something trivial that clears itself to something that needs attention.
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 alert checks for compressor prefill faults every 100ms.
Set: Compressor prefill will timeout during a prefill operation if the pressure derivative remains under 1 bar/second for 10 seconds.
Clear: Single drive-rail cycle
Note: A prefill operation is performed before opening the valves to an air spring or the reservoir. Prefill works by activating the compressor with the spring and reservoir valves closed, so that the gallery pressure increases. This reduces the change in pressure upon opening of the valves, similar to the precharge sequence for the high-voltage battery or on-board chargers.
Prefill will fail if:
a valve is open or leaking (pressure escapes from the gallery)
the compressor does not run
compressed air escapes before the valve block
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.