DI_a104_trailerBrakeBackupState
Trailer brake control reduced
What does the DI_a104_trailerBrakeBackupState alert mean?
The drive interface (DI) electronic control unit (ECU) detects Trailer Brake Control functionality may be reduced.
What you'll see in your Tesla
- Trailer brake control reduced
- Trailer brake functionality may be limited
What triggers it
Trailer brake control is in a backup state due to one or more invalid system input(s). Alert log signal data should provide more information on any invalid input(s) detected.
When it clears
This alert will clear on the drive cycle after trailer brake control is re-enabled or no condition affecting functionality is detected.
Potential impact
Trailer brake control is in a backup state that mimics a time delay brake controller. Trailer brakes are applied when the driver presses the brake. This can be reduced with the gain. The vehicle should be driven with caution.
Affected models
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