Back to 2004 Buick Century

2004 BUICK CENTURY

3.1L V6FWDAUTOMATICgas
2 active safety recalls on this vehicle — view recalls
Repairs0Labor473Torque2471Fluid6DTC779Battery0Maintenance0Recalls2
P0140moderate severityPowertrain

O2 Sensor Circuit No Activity Bank 1 Sensor 2

on 2004 Buick Century 3.1L V6 · FWD

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

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