EV Diagnostics
Source-backed diagnostic reference

P1151 EV diagnostic code

O2 Sensor Heater Circuit Signal Intermittent Bank 2 Sensor 1

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 Signal Intermittent Bank 2 Sensor 1 Source
  • FORD: Lack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2 Source
  • LINCOLN: Lack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2 Source
  • MAZDA: HO2S Bank 2 Sensor 1 Signal Below 0.45v AF Ratio Too Lean Source
  • MERCURY: Lack of Upstream Heated Oxygen Sensor Switch Sensor Indicates Lean Bank 2 Source
  • OTHER: Lack Of HO2S21 Switch - Sensor Indicates Lean Source
  • SUBARU: Rear Oxygen Sensor Heater Circuit High Input Source
  • VOLKSWAGEN: Bank 1 Long Term Fuel Trim Range 1 Lower Lean Limit Exceeded Source
  • GENERIC: Lack Of HO2S21 Switch - Sensor Indicates Lean Source

Search and canonical URL

Capitalization, underscores, hyphens, colons and spaces are normalized to this canonical code identity so alternate scan-tool formats do not create duplicate pages.