Why is My Number 10 Fuse Blowing When I Hook My Trailer Up to My 2006 Ford Van?

Updated 04/18/2025 | Published 04/17/2025

Question:

When I plug my C56020 into a trailer or my 7 way adapter, my number 10 fuse pops and I no longer have running lights. I have tested extensively and believe my C56020 is defective. I have read other reviews of people having the same problem.

asked by: Bry T

Expert Reply:

Hi Bry,

It looks like the issue might not be with the brake controller after all, but possibly with the wiring.

If your #10 fuse keeps blowing when you hook up your trailer to the CURT # C56020 T-Connector on your 2006 Ford van, it’s likely due to a short somewhere in the trailer’s wiring, especially in the running lights, which that fuse typically protects. Common culprits include pinched wires, corroded sockets, bad bulbs or LEDs, or a poor ground. Occasionally, the trailer plug might be miswired, or in rare cases, the CURT harness itself could be faulty or damaged.

A simple test: unplug the trailer and see if the fuse still blows. If it doesn’t, the problem is definitely on the trailer side. I recommend double-checking all wiring, especially near the lights and where it contacts the frame. Make sure all ground connections are solid. If you have a multimeter or trailer light tester, those can really help narrow it down.

I’d hate for you to go through a warranty return on the wiring harness only to hook up the new one and run into the same issue. Once you’ve checked the trailer wiring and bulbs, let me know if everything looks good, I’ll get you the warranty info.

Also, do you have another vehicle you can hook the trailer up to? That could be a quick way to confirm where the problem lies.

Let me know how it goes!

expert reply by: Kate F

Bry T.

4/17/2025

I have confirmed it is not the trailer. Connected another trailer and the fuse popped with that one too. I would like to make a warranty claim for the C56020

Kate F.

4/18/2025

@BryT When I looked at the order I noticed we were a little outside that 1 year warranty, but I was able to get it pushed through with some magic. An email was sent to you explaining how the warranty works, if you have any questions Bry, you know where to find me.