UMC family
UMC_a021_dataBus
Not Available
What does the UMC_a021_dataBus alert mean?
UMC microcontroller failed internal data bus self test
What you'll see in your Tesla
- Not Available
What triggers it
UMC microcontroller fails internal data bus self test
When it clears
UMC microcontroller passes an internal data bus self test
Potential impact
UMC will not operate until internal data bus passes self test
Affected models
Cybertruck
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
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