Turn signals cause all rear lights to flash?

1999 CHEVROLET SILVERADO
265,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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DAMARTIN22
  • MEMBER
  • 1 POST
When I turn my signal lights on either side it causes all lights in the rear of the truck to start flashing, even the third brake light flashes, and when I hit the brakes, the flashing stops. Also, the third brake light stays dimly lit.
Aug 30, 2022 at 5:07 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,267 POSTS
This sounds like a bad ground at the rear of the truck, or the trailer wiring connector is shorted out. Here are the wiring diagrams so you can see how the system works and the ground location so you can check it out and fix the problem.

Ground location - on spare tire hoist bracket, upper left kick panel

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.

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Aug 31, 2022 at 3:19 AM
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