Electrical problems with the cruise control, headlights and taillights

2005 KIA SORENTO
130,000 MILES • 2.4L • 6 CYL • 4WD • AUTOMATIC
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DOUGDARLAND
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  • 3 POSTS
My cruise control doesn’t work when the headlights are on. The headlights turn off and on with the key (as if they’re automatic, but they’re not supposed to be). The taillights cut out when the brakes are applied.
Nov 25, 2020 at 9:36 PM
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JACOBANDNICKOLAS
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Hi,

When you apply the brakes, do all lights turn off? Do the brake lights turn on?

I feel confident at this time that the cruise control issue is related to the brake light issue, but I need to know if the brake lights do turn on and the other rear light turn off.

Also, I want you to try something. Under the hood in the power distribution box, there is a relay called a TNS relay. Try switching it with another relay having the same part number and see if makes a difference. This relay could be the cause of most of the issues.

___________________

Pic 1 shows the relay in the wiring system. Pic 2 shows the location of the relay in the fuse/relay box.

Let me know what you find.

Joe



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Nov 26, 2020 at 3:07 PM