Troubleshooting Trailer Brakes Locking Up When Tow Vehicle Disconnected
Updated 12/22/2025 | Published 10/24/2024
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Question:
Why might my trailer brakes be locking up if it is NOT plugged into my truck?
asked by: Patti R
0
Expert Reply:
Hi Patti; the only way for your trailer brakes to lock up is if you have power running to them. Without the vehicle attached the only way for this to happen is if the brake output wire is getting power from your trailer batteries which is probably from a short in the wires. Take a tester like # PTW2993 and work your way along the brake output wire to find where power is crossing over and repair the short.
expert reply by:
Robin H
0
Product Page this Question was Asked From
Replacement Trailer Brake Magnet for 12" Brake Assemblies
- Accessories and Parts
- Trailer Brakes
- Electric Drum Brakes
- Brake Magnets
- 12 x 2 Inch
- Redline
more information >
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Robin H.
12/22/2025
Hey Patti, how did things go after you tested the brake output wire with the circuit tester? Knowing what you found with the short could help others figure out similar brake issues.