Cruise control fluctuates?

2021 KIA SOUL
50,000 MILES • 4 CYL • 2WD • AUTOMATIC
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CWHITE73
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  • 1 POST
Once I set my cruise control, instead of staying at the speed I set it at it fluctuates up to 5-7 miles faster / slower. Cruise control is supposed to maintain the speed it's set to correct?
May 21, 2023 at 8:17 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
It sounds like you may have a radar sensor that is going out which affects the cruise control. We should run a CAN scan; you can get a CAN scanner (Controller Area Network) which will work on most cars from Amazon.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ

and

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Here are the cruise control wiring diagrams so you can see how the system works. Check out the images (below). Please let us know what happens.
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Professional Diagram for 2CarPros Members
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Professional Diagram for 2CarPros Members
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Professional Diagram for 2CarPros Members
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Professional Diagram for 2CarPros Members
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Professional Diagram for 2CarPros Members
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May 22, 2023 at 10:30 AM
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