ESP family
ESP_a009_12VHardUndervoltage
ABS (anti-lock braking system) disabled
What does the ESP_a009_12VHardUndervoltage alert mean?
ESP/ABS unit voltage is low.
What you'll see in your Tesla
- ABS (anti-lock braking system) disabled
- Drive with caution
What triggers it
Voltage across pins 25->38 or 1->13 on the ESP connector below specification
When it clears
Voltage across pins 25->38, and 1->13 on the ESP connector meets specifications
Potential impact
ABS/TC/VDC disabled
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.