Code UI_a110 was reported by the “User interface” controller in the car. The letter “a” in the middle places it among entries of the alert type.
The application layer of the touchscreen. Most codes from here are everyday notices the car shows the driver — an open frunk, a door left ajar, a status message about some feature. They are not hardware faults.
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.
Dashcam experienced an error while freeing up space or creating a file
Dashcam cannot free up space or create new files
Radio tuner took longer than usual before operating
The Ecall audio configurator 'Ecall Digital microphone' test failed
Ecall digital microphone RMS amplitude is lower then EcallDigitalMicRMSThreshold (0.02)
Ecall digital microphone test has to pass
Backup camera initialization failed.
Failed to initialize the backup camera due to issue with communication on the /dev/video0 bus or other error condition.
Backup camera initializes successfuly.
A warning was posted on the bus created by the video pipeline.
Passenger or rear door (except MX falcon) open when gear is D/R/N. Triggers a continuous chime
Passenger or rear door (except for MX falcon door open which have their own alert) when gear is D/R/N
Shift into Park or close the door(s)
User Interface cluster display (QtCarCluster) has crashed and will reboot. A crashlog has been generated and will be uploaded to Sentry (if enabled for this vehicle). Check for its 'txid' in syslogs.
QtCarCluster has crashed and will reboot.
QtCarCluster resumes standard operation.
A bad/faulty USB device has been plugged into the system
A bad/faulty USB was plugged in and detected by the kernel
When user unplugs the faulty USB device
Critical warning bits are set in the NVMe smart log
Critical warning bits are turned on in the smart log
Critical warning bits are turned off in the smart log
NVMe subsystem reliability might be affected
Pending configuration changes will apply once the vehicle is parked
Vehicle has received a gateway configuration change while in gear
Infotainment system will reboot when vehicle parked with display(s) off
AMD i2c Bus 1 encountered a aborted transaction
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.