Back to 2002 Infiniti QX4

2002 INFINITI QX4

3.3L V6RWDAUTOMATICgas
6 active safety recalls on this vehicle — view recalls
Repairs0Labor498Torque3650Fluid7DTC705Battery0Maintenance0Recalls6
P0140moderate severityPowertrain

O2 Sensor Circuit No Activity Bank 1 Sensor 2

on 2002 Infiniti QX4 3.3L V6 · RWD

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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