Turn Signals Inoperative

1977 GMC Forward Control 7.4L Eng VIN Y, Automatic Trans, Trans Mfr CD 475/M40SECTION Turn Signals Inoperative

Turn on hazard system, if all lights operate, inspect for blown turn signal fuse or defective flasher. If fuse is open, check for shorts between fuse and lamps. If turn signal fuse and flasher are satisfactory, check wire terminals in harness connector for continuity and power feed to and from switch. To determine if switch is bad, connect a known good switch in column to chassis connector and operate switch by hand. If signals now operate, replace switch.

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.