brake lights not not working properly

1997 CHEVROLET CHEYENNE
315,000 MILES • V8 • 2WD • AUTOMATIC
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PAPITO84
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  • 1 POST
i own a 1997 chevy c-2500 pick up, the brake (stop) lights will only work when the truck is in reverse. i checked all the bulbs, fuses, and relays and they are all fine, what could it be?
May 21, 2011 at 5:49 PM
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JDL
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Check the grounds at the rear. Do the high-mount brake lites work ok? Your lower brake lites and turn signals use the same bulb filament, just not at the same time. Your lower brake lites are wired through the turn signal switch. At the right rear, dark green wire is voltage for that brake lite, black wire is ground. At left rear, yellow wire is voltage for brake lamp, black is ground.
May 21, 2011 at 6:26 PM
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JDL
  • ✓ASE Certified Mechanic
  • 16,098 POSTS
  • ASE Certified Mechanic
Diagram for lower brake lites.
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May 21, 2011 at 6:28 PM
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