1997 GMC Forward Control 5.7 R, AutomaticFACTORY OEM SERVICE PROCEDURE

Scan Tester

A variety of information is transmitted through Data Link Connector (DLC). This data is transmitted at a high frequency which requires a Tech 1 Scan Tester (94-00101A), appropriate cartridge kit and vehicle interface module kit, or other scan tester for interpretation. Several scan testers (scan tools) are available for diagnostic work. Scan testers other than Tech 1 scan tester will function and provide information for diagnostic work.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.