CP family
CP_a121_PLCRLY_lostCommsCP
Not Available
What does the CP_a121_PLCRLY_lostCommsCP alert mean?
The power line communication relay (PLCRLY) is no longer receiving messages from the charge port (CP) electronic control unit (ECU). This alert is used only by PLCRLY.
What you'll see in your Tesla
- Not Available
What triggers it
PLCRLY does not receive messages from the CP ECU within 10 times their expected rate of transmission.
When it clears
PLCRLY receives the expected messages from the CP ECU.
Potential impact
PLCRLYs on single-phase CP vehicles will not allow combined charging system (CCS) charging above 370A.
Affected models
Cybertruck
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
Semitruck
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