P0715moderate severityPowertrain

Input/Turbine Speed Sensor Circuit

on 2020 Subaru Legacy 2.5L H4 · AWD

What this code means

Malfunction in the transmission input speed sensor.

Symptoms

  • Check Engine Light
  • Harsh shifting
  • No shifting
  • Limp mode
  • Erratic speedometer

Common causes

  • Faulty input speed sensor
  • Wiring damage
  • Tone ring damage
  • Internal transmission damage

Diagnostic steps

  1. Test sensor output
  2. Check wiring
  3. Inspect connector
  4. Check for metallic debris on sensor

Repair notes

Replace input speed sensor. Check for trans fluid contamination.

Other Powertrain codes on this vehicle

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