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2002 BMW M3
3.2L I6 S54•RWD•AUTOMATIC•gas•S54B32
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor498Torque3157Fluid8DTC1267Battery1Maintenance0Recalls5
P0041moderate severityPowertrain

O2 Sensor Signals Swapped Bank 1 Sensor 2 / Bank 2 Sensor 2

on 2002 BMW M3 3.2L I6 S54 · RWD

What this code means

The downstream O2 sensor signals for Bank 1 and Bank 2 appear to be swapped.

Symptoms

  • Check Engine Light
  • Incorrect catalyst monitoring
  • Failed emissions

Common causes

  • Sensor connectors swapped
  • Wiring crossed after service

Diagnostic steps

  1. Verify downstream sensor connections
  2. Trace wiring to PCM

Repair notes

Correct the sensor connector routing.

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