EV Diagnostics
Source-backed diagnostic reference

P1139 EV diagnostic code

O2 Sensor Heater Circuit High Voltage Bank 1 Sensor 2

Reference status: This page preserves source-backed code definitions for discovery. Manufacturer/model applicability, repair steps and safety conclusions are not treated as verified unless a manufacturer-specific verified report is available.

Reference definitions

  • BMW: O2 Sensor Heater Circuit High Voltage Bank 1 Sensor 2 Source
  • BUICK: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • CADILLAC: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • CHEVY: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • CHRYSLER: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • FORD: Water In Fuel Indicator Circuit Malfunction Source
  • GM: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • GMC: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • LINCOLN: Water In Fuel Indicator Circuit Malfunction Source
  • MERCURY: Water In Fuel Indicator Circuit Malfunction Source
  • OLDSMOBILE: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • OTHER: Water In Fuel Indicator Circuit Malfunction Source
  • SATURN: HO2S Insufficient Switching Bank 1 Sensor 2 Source
  • SUBARU: Front Oxygen AF Sensor #1 Heater Circuit Performance Range Problem Source
  • VOLKSWAGEN: Long Term Fuel Trim Add Fuel Bank 2 System Too Rich Source

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