EV Diagnostics
Source-backed diagnostic reference

P1804 EV diagnostic code

Ground Control Relay

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: Ground Control Relay Source
  • CADILLAC: Ground Control Relay Source
  • CHEVY: Ground Control Relay Source
  • FORD: Transmission 4-Wheel Drive High Indicator Circuit Failure Source
  • GM: Ground Control Relay Source
  • GMC: Ground Control Relay Source
  • LINCOLN: Transmission 4-Wheel Drive High Indicator Circuit Failure Source
  • MERCURY: Transmission 4-Wheel Drive High Indicator Circuit Failure Source
  • OLDSMOBILE: Ground Control Relay Source
  • OTHER: Transmission 4-Wheel Drive High Indicator Circuit Failure Source
  • SATURN: Ground Control Relay Source

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