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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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Repairs0Labor551Torque4667Fluid8DTC919Battery1Maintenance0Recalls6
P1094moderate severityPowertrain

Tumble Generator Valve Circuit 1 Open

on 2020 Subaru Legacy 2.5L H4 · AWD

What this code means

The PCM has detected an open circuit in the Tumble Generator Valve 1 actuator circuit on the right-hand bank. The actuator motor cannot be driven due to the break in the electrical path.

Symptoms

  • Check Engine Light
  • TGV 1 RH does not operate
  • Minor efficiency and emissions impact

Common causes

  • Broken wire in TGV 1 actuator circuit
  • Disconnected TGV actuator connector
  • Corroded connector pins
  • Faulty TGV actuator with open motor winding
  • PCM driver circuit open

Diagnostic steps

  1. Test TGV 1 actuator motor resistance
  2. Inspect actuator connector for disconnection or corrosion
  3. Check wiring continuity from PCM to actuator
  4. Verify PCM output signal
  5. Swap actuators between banks to isolate fault

Repair notes

Repair the open circuit in the TGV actuator wiring or replace the actuator if the motor winding is open.

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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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