Back to 2014 Subaru Legacy

2014 SUBARU LEGACY

3.6L H6AWDCVTgas
10 active safety recalls on this vehicle — view recalls
Repairs0Labor504Torque4989Fluid9DTC903Battery0Maintenance0Recalls10
P0140moderate severityPowertrain

O2 Sensor Circuit No Activity Bank 1 Sensor 2

on 2014 Subaru Legacy 3.6L H6 · AWD

What this code means

The downstream O2 sensor on Bank 1 shows no switching activity.

Symptoms

  • Check Engine Light
  • No catalyst monitoring

Common causes

  • Faulty sensor
  • Heater circuit failure
  • Wiring open

Diagnostic steps

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

Repair notes

Replace downstream O2 sensor.

Other Powertrain codes on this vehicle

Building an app?
Free API access to all this data — 50 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →