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2002 INFINITI QX4

3.3L V6RWDAUTOMATICgas
6 active safety recalls on this vehicle — view recalls
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Repairs0Labor563Torque3468Fluid7DTC705Battery0Maintenance0Recalls6
P0056low severityPowertrain

HO2S Heater Control Circuit Bank 2 Sensor 2

on 2002 Infiniti QX4 3.3L V6 · RWD

What this code means

Malfunction in the heater circuit for the downstream O2 sensor on Bank 2.

Symptoms

  • Check Engine Light
  • Failed emissions
  • Poor catalyst monitoring

Common causes

  • Faulty sensor heater
  • Blown fuse
  • Wiring issue

Diagnostic steps

  1. Check fuse
  2. Test heater resistance
  3. Inspect wiring

Repair notes

Replace O2 sensor or repair wiring.

Other Powertrain codes on this vehicle

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