1997 GMC Sierra Headlight Switch

1997 GMC SIERRA
175,000 MILES • V8 • 4WD • AUTOMATIC
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SLB0668
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  • 1 POST
I have a 1997 GMC Sierra 4x4 Z71-the headlight switch has 3 positions -off, running lights and headlights. Recently the headlights would not come on when the headlight switch was turned to the on position. I replaced the headlight switch 3 days ago and now have the same problem. The brake lights, turn signals and running lights work when the switch is in the off position and the middle position but when turned to the on position the headlights go off. I have checked all the fuses on the dash and under the hood. I can not find any schematics for the headlight switch. Do you have any troubleshooting suggestions?
Mar 10, 2010 at 9:13 AM
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JDL
  • ✓ASE Certified Mechanic
  • 16,098 POSTS
  • ASE Certified Mechanic
hi, yellow wire in diagram, is voltage to dimmer switch. If neither high or low beam work, I'd check feed to and from the dimmer switch, if that is ok, suspect the dimmer switch.


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Mar 10, 2010 at 9:50 AM
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