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2020 SUBARU LEGACY
2.5L H4•AWD•CVT•gas
6 active safety recalls on this vehicle — view recalls
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Repairs0Labor489Torque4350Fluid9DTC1127Battery1Maintenance0Recalls6
C0123high severityChassis

Electronic Parking Brake Control Module

on 2020 Subaru Legacy 2.5L H4 · AWD

What this code means

Internal fault in the electronic parking brake control module.

Symptoms

  • EPB warning light on
  • EPB functions inoperative
  • Hill-hold not working
  • Auto-hold not functioning

Common causes

  • EPB module internal failure
  • Module software corruption
  • Power supply issue to module
  • CAN communication fault to module

Diagnostic steps

  1. Check module power supply and ground
  2. Scan for CAN communication codes
  3. Attempt module reset
  4. Check for software updates
  5. Test module inputs and outputs

Repair notes

Replace EPB control module. Requires programming and calibration.

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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