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2003 AUDI A6

2.7L Turbo V6AWDAUTOMATICgasturbo
7 active safety recalls on this vehicle — view recalls
Repairs0Labor500Torque2499Fluid9DTC718Battery0Maintenance0Recalls7
P0056low severityPowertrain

HO2S Heater Control Circuit Bank 2 Sensor 2

on 2003 Audi A6 2.7L Turbo V6 · AWD

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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