Diagnostic Aids

1997 Chevrolet Chevy Express G3500, Van Cargo, 6.5 FSECTION Diagnostic Aids
WARNING: This page is about a different car, the 1995 Pontiac Trans Sport, 1995 Oldsmobile Silhouette, and 1995 Chevrolet Lumina APV. However, it is still accessible from the selected car via links, so may be relevant.

An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside insulation. Check for:

  • Poor Connection Or Damaged Harness  Inspect control module harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness.
  • Intermittent Test  Observe IAT on Tech 1 while moving related connectors and wiring harness with warm engine running. If failure is induced, IAT display will change to a -40° temperature reading. This may assist in isolating location of malfunction.
Fig 1: Code P0112 Schematic (3.8L FWD Van) IAT Sensor Circuit Low Input
G94E66070
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:

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