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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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Repairs0Labor485Torque4342Fluid9DTC1881Battery1Maintenance0Recalls6
C1199moderate severityChassis

Abnormal Stop Light Switch Circuit

on 2020 Subaru Legacy 2.5L H4 · AWD

What this code means

The brake light switch circuit is sending an abnormal or inconsistent signal. Related to OBD code P0504 (brake switch correlation).

Symptoms

  • Brake lights inoperative or erratic
  • VDC/ABS light on
  • Cruise control disabled

Common causes

  • Faulty stop light switch
  • Blown brake light fuse
  • Wiring or connector fault
  • Misadjusted switch position

Diagnostic steps

  1. Test stop light switch operation
  2. Check brake light fuse
  3. Inspect switch wiring and connector
  4. Verify switch adjustment
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