Circuit Description

1999 GMC Forward Control 5.7 R, AutomaticSECTION Circuit Description

Camshaft Position (CMP) sensor is used to indicate camshaft position so that VCM can determine which cylinder is misfiring if misfire is present. CMP sensor also checks for properly installed high voltage switch. DTC will set when engine is running and CMP sensor reference pulse is not seen once every 6 revolutions.

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.