Back to 2009 Subaru Forester

2009 SUBARU FORESTER

2.5L H4AWDCVTgas
18 active safety recalls on this vehicle — view recalls
Repairs0Labor504Torque3865Fluid9DTC861Battery0Maintenance0Recalls18
P0154moderate severityPowertrain

O2 Sensor Circuit No Activity Bank 2 Sensor 1

on 2009 Subaru Forester 2.5L H4 · AWD

What this code means

No switching activity from the upstream O2 sensor on Bank 2.

Symptoms

  • Check Engine Light
  • Poor fuel economy

Common causes

  • Faulty sensor
  • Heater failure
  • Wiring open

Diagnostic steps

  1. Test sensor signal
  2. Check heater
  3. Inspect wiring

Repair notes

Replace O2 sensor.

Other Powertrain codes on this vehicle

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