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1999 AUDI A3

1.8L Turbo I4 QuattroFWDAUTOMATICgasturbo
Repairs0Labor595Torque2435Fluid6DTC645Battery0Maintenance0Recalls0
P0155low severityPowertrain

O2 Sensor Heater Circuit Bank 2 Sensor 1

on 1999 Audi A3 1.8L Turbo I4 Quattro · FWD

What this code means

Malfunction in the upstream O2 sensor heater on Bank 2.

Symptoms

  • Check Engine Light
  • Extended warmup emissions

Common causes

  • Faulty heater
  • Blown fuse
  • Wiring issue

Diagnostic steps

  1. Check fuse
  2. Test heater resistance
  3. Inspect wiring

Repair notes

Replace O2 sensor.

Other Powertrain codes on this vehicle

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