RCU family
RCU_a048_ESPFrLWSSLInvalid
Not Available
What does the RCU_a048_ESPFrLWSSLInvalid alert mean?
Front left wheel speed sensor signal is invalid.
What you'll see in your Tesla
- Not Available
What triggers it
The RCU receives the ESP_wheelSpeedFrL as Signal Not Available (SNA) for 100 milliseconds.
When it clears
The Redundant Control Unit (RCU) receives a valid ESP_wheelSpeedFrL signal for 100 milliseconds while the vehicle is parked.
Potential impact
There may be an issue with the transmitting Electronic Control Unit (ECU), the Integrated Dynamic Brake (IDB).
Affected models
Model Y 2025+
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