EV Diagnostics
Source-backed diagnostic reference

P1421 EV diagnostic code

Secondary Air System Bank 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: Secondary Air System Bank 1 Source
  • BUICK: Intake Air Low Pressure Switch Circuit High Voltage Source
  • CADILLAC: Intake Air Low Pressure Switch Circuit High Voltage Source
  • CHEVY: Intake Air Low Pressure Switch Circuit High Voltage Source
  • CHRYSLER: Intake Air Low Pressure Switch Circuit High Voltage Source
  • GM: Intake Air Low Pressure Switch Circuit High Voltage Source
  • GMC: Intake Air Low Pressure Switch Circuit High Voltage Source
  • OLDSMOBILE: Intake Air Low Pressure Switch Circuit High Voltage Source
  • OTHER: Catalyst Damage Source
  • PLYMOUTH: Intake Air Low Pressure Switch Circuit High Voltage Source
  • PONTIAC: Intake Air Low Pressure Switch Circuit High Voltage Source
  • SATURN: Intake Air Low Pressure Switch Circuit High Voltage Source
  • SUBARU: Exhaust Gas Recirculation Circuit High Input Source
  • VOLKSWAGEN: Secondary Air Injection Valve Circuit Short To Ground Source

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