Brake lights not working

2005 CADILLAC CTS
169,000 MILES • 3.6L • V6 • 2WD • AUTOMATIC
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SEMAJ BERRYMAN
  • MEMBER
  • 2 POSTS
My brake lights won't light up on my car, but the tail lights work. put a new brake light switch in and i changed the BAS fuse under the back seat and still no results.
Mar 11, 2019 at 3:01 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Good morning,

I attached a diagram for you to view. You need to check the voltage to the stop light switch. It uses a 5 volt reference voltage to send a signal to a module which controls the brake lights.

Roy
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Mar 11, 2019 at 3:39 AM
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