Diagnostic Aids

1994 Chevrolet Lumina BaseSECTION Diagnostic Aids

An intermittent problem may be caused by a poor connection, rubbed through wire insulation, or a wire broken inside insulation. Frequency of problem can be checked by using Enhanced Diagnostic feature of Tech 1.

Any circuit suspected of causing intermittent problem should be thoroughly checked for backed-out terminals, improper mating, broken connector locks, damaged terminals or poor terminal-to-wiring connections.

Fig 1: DTC 77 Schematic
G94A34686Courtesy of GENERAL MOTORS CORP.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.