P0155 O2 Sensor Heater Circuit (Bank 2 Sensor 1)

Powertrain Severity: Low Generic OBD-II

Fault in the heater circuit of the upstream oxygen sensor on bank 2.

Common causes

  • Burned-out heater
  • Blown fuse
  • Wiring damage

Symptoms

  • Check engine light

What to check

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

Manufacturers may add their own detail to generic codes. If your vehicle shows a different description for P0155, follow the service information for that make and model.

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