MyTeslaMate
DPB family

DPB_a224_brakeBoostLost

Power braking assist reduced

What does the DPB_a224_brakeBoostLost alert mean?

Brake boosting capability is lost in DPB system.

What you'll see in your Tesla

  • Power braking assist reduced
  • Braking may require increased effort

What triggers it

Plunger Separation Valve or Plunger Overshoot Valve inoperable (aka huge leakage rate present in plunger circuit) OR no brake fluid OR wrong plunger configuration (as held in EEPROM), Fault is raised if Active System Tests (component STS) detect a latent fault that might jeopardize the hydraulic backup functionality. The first occurence of the fault may only be detected right after the start of a new OtherCycle, when in full hydraulic system and at earliest if any brake event has been absent since the start of a new OtherCycle. The system reaction to the presence of the fault is DPB Hydraulic Backup (without brake boost).

When it clears

First ensure that DPB ECU has fallen asleep. Execute the start of a new OtherCycle. Wait for at least 30 s without exerting any brake intervention (i.e. no apply of the brake pedal, hand brake, APB, value added function or similar).

Potential impact

System will request Hydraulic Boost Compensation when driver pressed the brake pedal.

Affected models

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.