Curt wiring harness for towed vehicle problem

[acooledge]

I recently installed the Curt Towed Vehicle Wiring Harness on my 2023 Ford Ranger. Part number 58986, advertised a ‘plug and play’, no need to splice any wires.

Following the included instructions, first, I disconnected the battery, then I disconnected the plugs on the driver and passenger sides and inserted the plugs on the Curt wiring harness on my Ford Ranger. I also attached the ground. Then I plugged the 4-pin into my other pickup truck (simulated how I would plug it into my motorhome). All the lights seem to work, except that the amber turn signal didn't flash, the red taillight/brake light flashed instead. I could almost live with this. The main problem I had is that when I disconnected the 4-pin from my pickup truck (motorhome simulator), the brake lights didn't work on the Ranger (the vehicle that has the harness installed). Actually, the brake light would work the first time I pressed the brake pedal, but wouldn't work after the first time. I disconnected and reconnected the battery and then the brake lights worked. (Although, now the auto down on the drivers' window doesn't work). Not sure if I will use the harness or just a set of magnet base lights instead.

Anyone have any experience with this wiring harness?

Thanks, Andy

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[RangerBill]

I recently installed the Curt Towed Vehicle Wiring Harness on my 2023 Ford Ranger. Part number 58986, advertised a ‘plug and play’, no need to splice any wires.

Following the included instructions, first, I disconnected the battery, then I disconnected the plugs on the driver and passenger sides and inserted the plugs on the Curt wiring harness on my Ford Ranger. I also attached the ground. Then I plugged the 4-pin into my other pickup truck (simulated how I would plug it into my motorhome). All the lights seem to work, except that the amber turn signal didn't flash, the red taillight/brake light flashed instead. I could almost live with this. The main problem I had is that when I disconnected the 4-pin from my pickup truck (motorhome simulator), the brake lights didn't work on the Ranger (the vehicle that has the harness installed). Actually, the brake light would work the first time I pressed the brake pedal, but wouldn't work after the first time. I disconnected and reconnected the battery and then the brake lights worked. (Although, now the auto down on the drivers' window doesn't work). Not sure if I will use the harness or just a set of magnet base lights instead.

Anyone have any experience with this wiring harness?

Thanks, Andy

The window auto down function, is lost when the battery is disconnected. This is a normal occurrence. The owner's manual shows how to recalibrate the window so it works again.

If you are connecting two trucks together via the trailer wiring plugs, I wouldn't do that as damage may occur.

 

[Desert Sage]

I'm just getting ready to install Roadmaster brackets (RM 524459-5) on my 2020 Ranger, and I'll be using an Even Brake system (RM 9400) when I tow. I asked if I needed a "Brake-Lite Relay Kit" (RM-88400) and I was told I did need that. This is what they said: "The purpose of a brake light relay kit is to prevent your towed car's brake signal from overriding the turn signal that comes from your RV. When your towed vehicle is properly wired and connected to your RV, its indicator lights will illuminate as you engage the turn signals in your RV." This info might pertain to your situation- but I'm not sure- for I am not well rehearsed on the Curt tow wiring harness.

 

[acooledge]

The window auto down function, is lost when the battery is disconnected. This is a normal occurrence. The owner's manual shows how to recalibrate the window so it works again.

If you are connecting two trucks together via the trailer wiring plugs, I wouldn't do that as damage may occur.

Thanks for info on resetting the window function.

 

[D Fresh]

Lariat, XLT, or base?

The LED tails might be the issue. We've got a few guys here using the Ranger as a TOAD. They should be along shortly to help.

 

[OFC Ranger]

To get my rear rack light sequential turn signals to work properly you have to tap and wire directly to the tail lamps, the trailer wiring won't allow them to work properly. Something about the PMC.

With that said, they worked fine otherwise when tested on trailer wiring (stop, run light, regular blink turn).

So I don't know what to tell you in this case.

 

[Big Blue]

What you are seeing with the harness using the brake lights as the turn signals is what I would expect as that is how trailer lights are wired in the US. Curt says the harness protects the towed trucks system with diodes so you don’t back feed the trucks systems (read BCM) with foreign power from the towing vehicle. I may be all wet but that sounds a little scary to me with the current solid state systems.

 

[acooledge]

Lariat, XLT, or base?

The LED tails might be the issue. We've got a few guys here using the Ranger as a TOAD. They should be along shortly to help.

XLT

 

[D Fresh]

XLT

With LED taillights or incandescent?

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