EV Diagnostics
Source-backed diagnostic reference

P1817 EV diagnostic code

TFP Valve Position Switch Reverse With Drive 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: TFP Valve Position Switch Reverse With Drive Ratio Source
  • CADILLAC: TFP Valve Position Switch Reverse With Drive Ratio Source
  • CHEVY: TFP Valve Position Switch Reverse With Drive Ratio Source
  • GM: TFP Valve Position Switch Reverse With Drive Ratio Source
  • GMC: TFP Valve Position Switch Reverse With Drive Ratio Source
  • OLDSMOBILE: TFP Valve Position Switch Reverse With Drive Ratio Source
  • OTHER: Transmission Neutral Safety Switch Open Circuit Source
  • SATURN: TFP Valve Position Switch Reverse With Drive Ratio Source

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