EV Diagnostics
Source-backed diagnostic reference

P1664 EV diagnostic code

1-4 Upshift Lamp Control Circuit

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: 1-4 Upshift Lamp Control Circuit Source
  • CADILLAC: 1-4 Upshift Lamp Control Circuit Source
  • CHEVY: 1-4 Upshift Lamp Control Circuit Source
  • GM: 1 4 Upshift Lamp Control Circuit Source
  • GMC: 1 4 Upshift Lamp Control Circuit Source
  • OLDSMOBILE: 1-4 Upshift Lamp Control Circuit Source
  • SATURN: 1-4 Upshift Lamp Control Circuit Source

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