EPASTS family
EPASTS_a123_imcmCommErr
Not Available
What does the EPASTS_a123_imcmCommErr alert mean?
This alert is reported when there is a Inter-MCU comm failure or other side is not communicating (UV or other failure).
What you'll see in your Tesla
- Not Available
What triggers it
The signal is unavailable because checksum error, or the signal is unavailable because Alive counter error, or Timeout (no frame arrived), or Frame size is out of range.
When it clears
Perform EPAS Software update.
Potential impact
EPAS A and B sides are not able to communicate. Steering assist reduced or might be unavailable.
Affected models
Model Y
Model Y 2025+
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