MyTeslaMate
DPB family

DPB_a091_MRGPathTestFault

Power braking assist reduced

What does the DPB_a091_MRGPathTestFault alert mean?

The control over MRG via EN_HY or MRAUC or both does not work.

What you'll see in your Tesla

  • Power braking assist reduced
  • Braking may require increased effort

What triggers it

MRG is either always switched ON or Not able to Switch OFF when Hydraulic Enable or MRA control is pulled LOW.

When it clears

No internal issue is detected after changing operation cycle. If the condition persists, the DPB module may require replacement.

Potential impact

System will be running in fully degraded state. Braking may require increased effort. Hydraulic Boost Compensation will be triggered when driver pressed brake pedal.

Affected models

Model Y 2025+

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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.