2020 Infiniti QX80 LimitedFACTORY OEM SERVICE PROCEDURE

DTC Detection Logic

The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst (manifold) causes the longer switching time. To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the maximum voltage of the sensor is sufficiently high during various driving conditions such as fuel cut.

GNSPJSBIA4446EL446Courtesy of NISSAN NORTH AMERICA, INC.

SYMBOL

: 0.71 V

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P2271

O2 sensor signal bank 1 sensor 2

[O2 sensor signal biased/stuck rich bank 1 sensor 2]

  • The maximum voltage from the sensor does not reach the specified voltage.
  • ECM detects the heated oxygen sensor 2 heater circuit is short to ground.
  • Harness or connectors

    (The heated oxygen sensor 2 circuit is open or shorted)

  • Heated oxygen sensor 2
  • Fuel pressure
  • Fuel injector
  • Intake air leaks
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.