ESP family
ESP_a104_hbcEnabled
Not Available
What does the ESP_a104_hbcEnabled alert mean?
ESP is providing hydraulic boost due to power brakes failure
What you'll see in your Tesla
- Not Available
What triggers it
ESP has lost communication with the iBooster, or iBooster has lost the ability to support brake boost
When it clears
Check iBooster status and traffic on the PARTY and CHASSIS bus
Potential impact
Brake boost functionality degraded
Affected models
Cybertruck
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
Track your Tesla's alerts automatically
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.