RCU family
RCU_a003_pumpMotorFault
Backup power braking assist unavailable
What does the RCU_a003_pumpMotorFault alert mean?
The Redundant Control Unit (RCU) has experienced a pump motor issue.
What you'll see in your Tesla
- Backup power braking assist unavailable
- OK to drive - Schedule service
What triggers it
The RCU has detected a motor power line open or short, the motor is stuck, or the motor built-in self test has failed.
When it clears
The RCU pump motor startup checks pass after the RCU is power cycled. If the issue persists, the RCU may need to be replaced.
Potential impact
The RCU may not be able to perform backup power braking assist.
Affected models
Model Y 2025+
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Alerts like this reach MyTeslaMate through your car's Tesla telemetry API. MyTeslaMate logs every alert your Tesla reports and turns it into readable history and real-time notifications — hosted TeslaMate with no server to run.