Code APP_w294 was reported by the “Autopilot — application layer” controller in the car. The letter “w” in the middle places it among entries of the warning type.
The application layer of Autopilot. Drives adaptive cruise control, lane keeping, lane changes and sign recognition. Faults here usually mean an assistance feature switched itself off temporarily — typically due to poor visibility or incomplete camera calibration.
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.
Autopark Rear Measurements on abort/completion
Fisheye camera initialization failed
Autopark space is found but prerequisites are not met, unmet prerequisites are flagged in payload
Messages from Steering Column Control Module (SCCM) ecu are missing on vehicle bus
One or more SCCM messages on vehicle bus are missing
AP starts receiving SCCM messages again
Driver Accel Pedal Override on autopilot
Driver overrides Adaptive cruise control (ACC) with accel pedal for at least 10 seconds
After user stops overriding or ACC is disabled
Braking will not be applied if override is detected
Messages from VCLEFT ecu are missing on party bus
One or more VCLEFT messages on party bus are missing
AP starts receiving VCLEFT messages again
Main camera initialization failed
SC_STATUS message is not received by Autopilot
AP starts receiving SC messages at periodic rate
Some autopilot features like Autopark are not available
Correctable/uncorrectable errors are non-zero
After 1 second if errors are zero
None as the feature is not enabled in production
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.