Troubleshooting Tekonsha Prodigy P3 Not Working When Truck is Turned On

Updated 02/20/2025 | Published 02/16/2025

Question:

I am having an issue with the controller saying no trailer connected and I get no trailer breaks when the truck is on. When the truck is off it shows connected and will apply the breaks on the trailer. It was working fine the day it was installed but the next morning it started doing the above. Is there something to remedy this?

asked by: Ray

No Trailer Connected on P3
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P3 Working With Truck Off
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Expert Reply:

Hey Ray! That is certainly unusual behavior. Since the Prodigy P3 # 90195 shows it is not connected when the truck is on I would start by checking the vehicle side connector. It sounds like there could be some corrosion causing the issue. I'm not sure how the 7-way functions on your truck but if you don't have power to other functions when the truck is off and do when it is on I could see that causing a problem if power carries over through corrosion.

The other thing I would be looking for is a bad ground. Start by double checking the P3 and then double check your other ground connections to see what you find. They should all be secure on a clean, bare metal surface. It wouldn't hurt to check the trailer connector for debris or corrosion as well just to be sure.

expert reply by: Robin H