EV Diagnostics
Source-backed diagnostic reference

P1800 EV diagnostic code

TCM Power Control Relay Circuit Open

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: TCM Power Control Relay Circuit Open Source
  • CADILLAC: TCM Power Control Relay Circuit Open Source
  • CHEVY: TCM Power Control Relay Circuit Open Source
  • GM: TCM Power Control Relay Circuit Open Source
  • GMC: TCM Power Control Relay Circuit Open Source
  • OLDSMOBILE: TCM Power Control Relay Circuit Open Source
  • OTHER: Transmission Clutch Interlock Safety Switch Circuit Failure Source
  • SATURN: TCM Power Control Relay Circuit Open Source
  • GENERIC: Transmission Clutch Interlock Safety Switch Circuit Failure Source

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