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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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Repairs0Labor528Torque4602Fluid8DTC919Battery1Maintenance0Recalls6
P1100moderate severityPowertrain

Starter Switch Circuit Malfunction

on 2020 Subaru Legacy 2.5L H4 · AWD

What this code means

The PCM has detected a malfunction in the starter switch circuit. The signal from the ignition switch indicating a start request is not being received correctly by the PCM.

Symptoms

  • Check Engine Light
  • PCM may not recognize engine cranking state
  • Fuel and ignition timing strategy may be incorrect during start
  • Extended crank time

Common causes

  • Faulty ignition switch
  • Wiring issue in starter switch signal circuit
  • Corroded ignition switch connector
  • Neutral safety switch issue affecting start signal
  • PCM input circuit fault

Diagnostic steps

  1. Check starter switch signal on scan tool during cranking
  2. Inspect ignition switch connector
  3. Test starter switch circuit wiring for continuity
  4. Check neutral safety switch
  5. Verify PCM receives crank signal

Repair notes

Repair the ignition switch signal circuit or replace the ignition switch if faulty.

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