EPASTS family
EPASTS_a126_mcusscMonbistMiaErr
Not Available
What does the EPASTS_a126_mcusscMonbistMiaErr alert mean?
This alert is reported by MCUSafetyStartupChecks_TC3x (MCUSSC) component when the Secondary Monitor and Standby SMU Built in Self Test failure, MCU failure
What you'll see in your Tesla
- Not Available
What triggers it
EPAS secondary monitor and standby SMU BIST timeout
When it clears
EPAS HW failure. EPAS power cycle N times and if persists, the gear needs to be changed.
Potential impact
EPAS full loss of assist
Affected models
Model Y
Model Y 2025+
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