Troubleshooting Brake Controller with OL Code when Brakes are Applied
Updated 04/28/2025 | Published 09/04/2018 >
Question:
When applying controller signals OL
asked by: Frederick L
Expert Reply:
If you check out the attached instructions for the Curt TriFlex Trailer Brake Controller # C24VV you can see that the OL code you are getting means that there is an "Overloaded output circuit, trailer brake system fault".
Whichever controller you have the problem and solution is the same. You have a short on your brake signal circuit from your brake controller to your trailer brakes which is causing too much power draw.
Check both the tow vehicle and trailer connectors and make sure they are clean and free of corrosion and debris. If they look good move on to the actual wiring and grounds for the brake circuit and your brake magnets. Make sure the wiring is undamaged and your grounds are securely connected to a clean, bare-metal surface. When you fix this it will fix your code.
Product Page this Question was Asked From
Curt TriFlex NEXT Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Plug-In
- Under-Dash Box
- Under-Dash
- Up to 4 Axles
- LCD Display
- Single Trailer Only
- CURT
more information >
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Dave P.
4/27/2024
I get OL signal without a trailer hooked up. Any comments?