EV Diagnostics
Source-backed diagnostic reference

P1871 EV diagnostic code

Undefined Gear Ratio

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

  • BUICK: Undefined Gear Ratio Source
  • CADILLAC: Undefined Gear Ratio Source
  • CHEVY: Undefined Gear Ratio Source
  • GM: Undefined Gear Ratio Source
  • GMC: Undefined Gear Ratio Source
  • OLDSMOBILE: Undefined Gear Ratio Source
  • OTHER: Transmission Mechanical Transfer Case 4x4 Switch Circuit Short To Battery Source
  • SATURN: Undefined Gear Ratio Source

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