All brake lights including the third light are not working and the ESC light is on

2012 KIA OPTIMA
100,000 MILES • 2.4L
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KEVST82
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  • 2 POSTS
I replaced bulbs. If I take out the 2 rear bulbs, the third brake light will work and ESC light goes off. With the pedal depressed, as soon as I put either of the rear light bulbs in, the third light goes out. I checked the 2 grounds behind the rear seat and they looked good. If I test the sockets of the rear lights, there is power supplied when the brake pedal is depressed. Any ideas?
Nov 3, 2020 at 1:58 PM
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DANNY L
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  • 5,648 POSTS
Hello, I'm Danny.

It sounds like you might be having an issue with the brake light switch. I've attached a picture below of its location. Hope this helps and thanks for using 2CarPros.
Nov 3, 2020 at 2:05 PM
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KEVST82
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  • 2 POSTS
I have replaced bulbs, the brake light switch and the BCM with no change. When the brake pedal is depressed, there is power that is getting to the brake lights. The power is just cut when the bulbs are put into the sockets.
Nov 5, 2020 at 4:56 AM
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JACOBANDNICKOLAS
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  • 110,175 POSTS
Hi,

A bad ground can cause this to happen. I attached a portion of the wiring schematic. Note that all of the brake light grounds are in the same location. Check there for any issues.

Note: I am basing this on the idea that when the bulbs are installed, you aren't blowing a fuse.

Let us know.
Joe
Nov 6, 2020 at 7:02 PM