EV Diagnostics
Source-backed diagnostic reference

P1138 EV diagnostic code

O2 Sensor Heater Circuit Low 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 Low Voltage Bank 1 Sensor 2 Source
  • BUICK: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • CADILLAC: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • CHEVY: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • CHRYSLER: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • FORD: Lack of Downstream Heated Oxygen Sensor Switch Sensor Indicates Rich Bank 1 Source
  • GM: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • GMC: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • JAGUAR: Lack Of HO2S12 Switches Sensor Indicates Rich Source
  • LINCOLN: Lack of Downstream Heated Oxygen Sensor Switch Sensor Indicates Rich Bank 1 Source
  • MAZDA: HO2S Bank 1 Sensor 2 Signal Above 0.45v AF Ratio Too Rich Source
  • MERCURY: Lack of Downstream Heated Oxygen Sensor Switch Sensor Indicates Rich Bank 1 Source
  • OLDSMOBILE: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • OTHER: Lack Of HO2S12 Switch - Sensor Indicates Rich Source
  • SATURN: HO2S Bank 1 Sensor 2 Rich Or High Voltage Source
  • VOLKSWAGEN: Long Term Fuel Trim Add Fuel Bank 2 System Too Lean Source

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