why do my tail and break lights go out when i turn my headlights on ?

1990 GMC SUBURBAN
150,000 MILES
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JOE MARTYNSKI
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  • 1 POST
my breaklights work only when my headlights are not on.
Sep 25, 2012 at 11:49 PM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
check the ground and circuit board in rear. the ground is left hand rear of frame
Sep 26, 2012 at 12:32 AM
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BLONDIE52966
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  • 1 POST
C130 Martynski from WI?
Jan 26, 2013 at 5:00 PM
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