DI family
DI_a129_epbNotApplied
Parking brake not set
What does the DI_a129_epbNotApplied alert mean?
The drive interface (DI) electronic control unit (ECU) detects a condition that prevents the electronic parking brake (EPB) from being set while the vehicle is not moving.
What you'll see in your Tesla
- Parking brake not set
- Vehicle may be free rolling
What triggers it
The DI ECU detects a condition that prevents it from setting the EPB.
When it clears
The DI ECU detects that the condition clears.
Potential impact
The EPB is not applied, and the vehicle may be free rolling.
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.