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1998 AUDI A3

1.6L I4FWDAUTOMATICgas
Repairs0Labor472Torque2472Fluid6DTC645Battery0Maintenance0Recalls0
P0056low severityPowertrain

HO2S Heater Control Circuit Bank 2 Sensor 2

on 1998 Audi A3 1.6L I4 · FWD

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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