Hello fellow DIYers. I installed the curt hitch on my '13 Fit Sport with a manual trans.

I also installed the plug and play wiring kit. I recently bought a small 4x8 trailer to help with an upcoming move and when I plugged in the trailer wiring NOTHING lit up. This is a brand new trailer, and when I plugged it into another vehicle at the seller's house all lights worked fine.

Well, I was stuck in WI in 0 degree weather at night towing a trailer with no lights, so I went straight to Walmart and bought another wiring kit, then spliced the trailer tail lights straight into the curt harness, and the lights came on.

THE PLOT THICKENS: I started to pull out of the parking lot and my throttle cuts out completely. This kept happening every few seconds, the throttle would cut out for a few seconds and come back on, obviously too dangerous to drive. I had no check engine light or anything. I then unplugged the harness again, and the car was completely fine. I plugged it back in, turned OFF my headlights (so the trailer lights were off too), and drove around the parking lot without issues.

I drove the trailer home with no lights on it (but lights on the vehicle). I removed the Curt wiring harness and am trying to figure out what's going on.

The ONLY thing I can think of is that the trailer lights draw too much power for the Fit's small alternator, causing power to cut to the injectors, spark plugs, or just the throttle. I bought a trailer plug tester so tonight I'll hook the harness back up and see if the Curt harness has power. If it doesn't, I may have to buy some LED lights and wire them straight into my tails. If it does have power, I will try buying LED bulbs for all the trailer lights and see if that decreases the load enough for the car to power them.

I've read about people towing a uhaul with their fit without this issue, so I'm really stumped, other than my hypothesis above.

Any advice or ideas? I know towing the trailer across the country with no lights isn't an option. I just can't think of any reason the plug and play curt kit would be faulty, nor do I understand how the tail lights could cause the aforementioned electrical issue when it seems nobody else has ever experienced this.

 

No ideas? Someone has to know more about electrical systems than me...

 

not too sure what's going on with yours but I have a Curt #56011 wiring kit on mine(2008 GD3 Sport) and have never had issues. Maybe a flaw in your wiring kit module? Ground issue?

 

I reinstalled the Curt wiring kit and bought a wiring tester (the little plug with LED lights). The wiring is working as it should, just does not power the trailer.

I believe my original thought that the trailer lights draw too much power was correct. I am going to buy an LED light kit for the trailer and remove the old kit.

 

So wait, the LED tester shows the unit is working correctly? What is the lighting units power connected to? Directly to the battery? Fused at 15 amps?

If yes to all the above, then there was a short on your trailer that should have popped that fuse. Now if you connected the light unit to say an existing circuit in the aux fuse panel inder the dash that say had to do with some other system, and it overloaded, then that would cause the failure you had. 15 amps is more than plenty to drive incandescent lights on a trailer.

We need to know more about your setup. Im jealous of your plug and play capability of the light unit. The GK 3rd gen has no such possibility. I had to solder and splice into the factory harness to get a trailer light unit to work with the car!

 

Thanks for the response!

The setup is just a plug and play Curt wiring harness. Nobody else has had issues with the same setup that I have been able to find- they use the same kit and plug into a Uhaul without issue. There is no auxiliary power or separate fuse, nor is there a place in the harness wiring to add aux power.

The trailer lights work fine when plugged into other vehicles (the seller's truck and my Jeep Cherokee) so I don't see how a short could be at fault.

I ordered a set of LED trailer lights that will be here tomorrow night. I will plug them in separately first, to make sure they work, then install on the trailer. Why the Fit doesn't seem able to power all the incandescent trailer lights is a real mystery.

 

What is the sku or unit you have for the trailer light wiring?

If its the 56011 from Curt, its 5 amps max running for stop/turn lights and 5 amps max for running lights. There is no external power source for this converter box. With incandescent bulbs you may be over the max amperage the stock harness can handle. You need a powered converter box.

See link below. If you did overload your oem light circuits once you research, you need a better converter, not necessarily LED lights, which are better lights, but not the best solution to your problem.

https://www.etrailer.com/Custom-Fit-Vehicle-Wiring/Honda/Fit/2013/HM11143165.html?vehicleid=20131172991

 

It is the 56011. Since LEDs draw so much less power won't they be under the amperage and therefore solve the problem? Also, they will solve it at a lower cost ($20) vs another converter ($40+).

 

Potentially yes. LEDs draw way less power. Powered converters are the best tool for such an application. The wire gauge for the lights in the Fits are so thin, like 22AWG that any extra load would overload the wire itself and the circuit feeding it. Its a cheap converter, and limits you to running only LED lights. Should you haul a trailer with incandescents, which is possible, you will run into problems.

I have LEDS stock on my Sure Trac 5x8. I still got a powered converter anyway because I've seen electrical issues like yours cause major pain points, and possible permanent damage with expensive repair. Whats the axiom, "buy once, cry once."




Sure Trac 5x8 Trailer 02



Sure Trac 5x8 Trailer 01



Tailgating Party with Trailer.

 

Where did you find a powered converter? Was it still plug and play? I only really need to tow ONCE, to move from Chicago back to Tampa, then I am selling the trailer, so longer term I'm not so concerned as long as the lights I am getting today will work.

The converter came with my Curt hitch and when I looked online I didn't find any powered converters for it.

 

Here is the converter i used

http://www.etrailer.com/Custom-Fit-Vehicle-Wiring/Honda/Fit/2017/119190KIT.html

 

I just finished wiring up the LED lights. Was actually quite easy since I just cut the existing lights off and soldered in the new ones. Converter has no trouble powering the new lights so all is well for the cross country move tomorrow.

 

Sweet deal! Glad it worked out! Looks like the Honda Fit lighting circuits cannot handle incandescent lights without a powered converter.

Something for others to keep in mind that if they haul a trailer with incandescent lights, they will need to get a powered converter, or swap out the incandescents for LEDS and use the unpowered one. Seems to me the costing is about the same between LED/unpowered and incandescent/powered.