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2021 AUDI A3

2.0L Turbo I4AWDAUTOMATICgasturbo
Repairs0Labor507Torque3838Fluid9DTC924Battery0Maintenance0Recalls0
P0140moderate severityPowertrain

O2 Sensor Circuit No Activity Bank 1 Sensor 2

on 2021 Audi A3 2.0L Turbo I4 · AWD

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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