Adapter 4-Pole to 7-Pole and 4-Pole
(600 reviews)
Price: $55.59
In Stock
Adapter 4-Pole to 7-Pole and 4-Pole
Item # 37185
Retail:$65.39
Our Price: $55.59
You Save: 15%
In Stock
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- Reviews (600)
- Q & A (0)
- Photos
Hopkins Trailer Wiring - 37185
- Wiring Adapters
- Multi-Function Adapter
- 4 Flat
- 7 Round - Blade
- Plug and Lead
- 4 Flat
- Hopkins
Adapter converts from 4 pole wiring on vehicle to 7-pole round plug and 4-pole flat. Additional wire leads for brake, power and accessory.
Features:
- Adapter converts from 4-pole wiring on your vehicle to 7-pole round plug and 4-pole flat wiring for trailer side
- Adds additional wire leads for brakes, power, and accessory wiring
- Wire functions:
- White - ground
- Blue - brake
- Black - hot lead - 12 volt power supply
- Purple - auxiliary
- Mounting bracket included
Specs:
- Connector measures 3" x 3"
- Distance between vehicle mounting holes: 2-3/16"
- 90-Day limited warranty
Wire Functions:
White: Ground
Blue: Brake
Black: "Hot" Lead - 12V power supply
Purple: Aux. - Reverse Lights etc.
Note: If you run the hot lead (black wire), you will need a circuit breaker, for example 9510 (sold separately), between the adapter and the battery itself.
47185B Adapter 4-Pole to 7-Pole and 4-Pole - Hopkins # 47185B, TAP # 37185
California residents: click here
Customer Satisfaction Score:
96% were satisfied with this product
4% of customers were not satisfied
- Wrong item was ordered
- Product did not meet expectations
- etrailer mistake
Customer Reviews
Adapter 4-Pole to 7-Pole and 4-Pole - 37185
Average Customer Rating: 4.8 out of 5 stars (600 Customer Reviews)
Adapter converts from 4 pole wiring on vehicle to 7-pole round plug and 4-pole flat. Additional wire leads for brake, power and accessory.by: R. Fulcher07/10/2023
Really nice trailer wiring adapter. Very easy install. Takes about 30 minutes with all the tools needed. Drill, 7/64 bit for pilot holes to mount the bracket, flat blade screwdriver and 11/32 nut driver and two #10 self tapping metal screws with locking split washers and a couple zip ties to tidy up the wiring harness.
by: John12/11/2020
Installed on our 2019 Edge ST with no significant issues. Works as expected, has reasonable required depth behind connector for ease of install, and the bracket was quite adaptable after some bending and cutting. Not impressed with the overall feel, though - plastic seems lightweight and cover hinge pin is already rusting after two winter weeks in western PA. Long term durability tbd.
by: Nick 07/20/2023
Worked great in tandem with a new wiring harness. Still working after a year of use.
by: Jack W09/07/2023
This company is amazing as they offer an incredible vast inventory of most anything one can imagine relating to trailers. They sent a nice email confirming the order and notice of being shipped, which arrived in just three days.
by: Tom03/27/2013
The product itself is very well made. The 4-pin connector is molded into the product and very sturdy. The 7-pin connector is held closed by a spring and has a foam gasket to keep water out. The 4-pin wiring is only about a foot long, and the additional 7-pin wiring is a bit longer. I do not have a brake controller (but do borrow a trailer with the 7-pin wiring), so I removed those wires. I also hard-wired all the connections, so I can't speak to the quality of the 4-pin vehicle connector.
The mounting bracket is thin steel, which worked well for me, as I had to bend the mounting plate to make it work for my installation. The paint on the mounting plate appears to be high quality as I bent the plate and banged it around quite a bit during install and did not nick the paint. The plate is drilled so that is can be mounted with the 7-pin hinge facing up, down, left or right.
The hardware is zinc coated, so it should hold up well to the weather. I went ahead and replaced it with SS to make sure. I also replaced the standard nuts with SS nylon lock nuts to make sure nothing would back out due to vibration. If you plan on using the supplied hardware, I would strongly suggest Loctite on the mounting nuts.
I installed this on a CX-5 with hitch # 87623, wiring adapter # C56011 and hitch cover # I-728. Over all a very clean installation. The connector is completely hidden inside the bumper, but easily accessible.
by: Cameron D.04/30/2019
This was exactly what I was looking for to add to my 2017 Ford Expedition! It is an easy to install plug-n-play product to convert a factory 4-pin connector to a 4/7-pin connector.
I plugged the 4-pin in, connected the brake wire, and grounded it. Ignoring the auxiliary + power cables, everything worked on the first test. The 4-pin connection was given some dielectric and wrapped with electrical tape to keep it sealed from the elements, and the slack was zip tied to secure it.
I still need to give it some finishing touches (fill the bracket gap with some black silicone, maybe find the reverse and/or power lines), but it lets me haul my camper!
by: Peter Foronda07/09/2018
2018 wrangler unlimited Sport S. Without trailer wiring. Completed installation today. Used a 4 flat along with a 7 pin converter. Works and fit perfectly. Very hot day and work slowly and carefully. Very satisfied . Great folks at etrailer. Great products, great quality and prices. I'm a several time repeat customer and couldn't be more satisfied.
4 pin harness Was a 56407 and the 7 pin adapter was a 37185.
by: Dale07/25/2023
Just like always from etrailer, the right product, right on time, and right on the money.
by: Hal04/15/2018
I recently installed the 4-pole to 7-pole adapter on my 2015 Highlander. My first install worked OK, but I ran into a ground clearance issue using the original mounting location. Etrailer suggested using a 2 1/2" mounting box to relocated the connector. Part number 18156 worked perfectly.
by: Mackenzie10/18/2019
The trailer wiring adapter was perfect and shipped in no time. Looks great on my ford ranger. Im very happy.
Was 4 flat only and now I can light my 7 way 18' trailer and have the capacity to add a brake controller (which I will add)
by: Daniel03/02/2023
Used on my wifes van and works great with our camper. Only complaint is wish is had a way to stabelize to the vehicle a bit better two screws at the top are all that hold it on to the van.
by: John08/28/2023
I had a great experience. Got the product with no problems.
by: John01/21/2013
Just what I need to tow an RV trailer. Also has a four flat connector. Very easy to install on the 18136 bracket.
by: Adam04/28/2018
Installed on a 2010 Ridgeline. Just what I needed at a great price. Install was a breeze. etrailer is the best place to find all the stuff that auto dealers rip you for. Good quality and the customer service is above reproach.
by: Rick Holbrook08/31/2020
I bought this so I can convert my dad's trailer to pull I only had a four and I needed a seven so I went and used a four to make it a seven. It's a very nice product it's got nice rubber grommets to keep everything protected.
by: Randall06/14/2020
2012 Chevrolet Express..Looks and works great! Easy install..2 1/8" hole saw for center, 3/16" drill bit for mounting screws. Thank you etrailer!
by: Scott 09/06/2023
Thank you so much! You all are so attentive and helpful!
by: Royal D.11/08/2013
I use these adapters to install 7-way connectors on trucks that have no factory trailer wiring provisions.
by: Robert10/15/2022
The personal service Steve provided was great. He went above what I expected and answered all my questions. He asked all the right questions and verified this part was correct for the brake controlled I had. He went step by step over the correct wiring to ensure I maintained all the functionality of my current system.
by: William N04/25/2018
Wow after Charles great advice this was so simple to install, [online] video was point on and the hardest thing was finding the reverse wire.
Thanks so much for a good product and excellent advice, here is the pic after install!
by: Michael 05/13/2023
Jessica M is the best , very pleasing and helpful . I will always ask for her e trailer products are always QUALITY
by: Pete K.07/12/2020
They shipped my harness immediately to UPS. After two weeks I did not receive it, so I called the guy said it would be there Friday or Saturday, Saturday was the fourth so I knew that was gonna happen. So I waited till Thursday and called and talked to Amy E., She was great, she Found out that my harness was sent back to them. Amy re-ordered my harness, I received it on Saturday! The harness fit perfectly! So I am going to give them an excellent review! My patients was worth wait ,because it was exactly what I needed! Thank you so much Amy I appreciate all the help.
by: Greg S01/15/2023
Perfect fit. The wire leads were long enough to connect to the oem harness
by: David R05/09/2020
Great product and description. Installation was very easy and smooth. Everything lined up, the installation video was on point
by: Mike02/20/2022
Your information on how to connect to controller wasted a lot of time on the adapter under the steering column. In my Ford Expedition, the existing connector was plugged in and Brown not Gray. It was a simple swap. Instead, I tore apart panels under dash looking for an unconnected gray plug. Also you should sell the proper adapter for the rear end connector also. A simple plug swap vs. cutting 2 wires on Ford's wiring harness wires and using butt connectors would save so much time. Also, having a long purple wire for backup lights (not used very often) and short leads for hot and electric brakes was really stupid. I had to add 1 ft of wire to each - more butt connectors and potential for failure.
Jenny N.
2/28/2022
It is unusual that the 21 Ford Expedition will come with an adapter that is already plugged in under the dash to the left of the steering column. We do have listed as a tech tip for part # 37185 that an additional length of wire may be necessary to connect the 7-Way socket of part 37185 to the vehicles tow package wires which are along the rear frame rail.
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See what our Experts say about this Hopkins Trailer Wiring
- Is There a Difference Between 7-Way RV Standard and TraditionalThe only difference between 7-way traditional and standard wiring is the colors of the wires. The functions and pin outs are the same so an adapter isn't needed. What you have is possibly a short between the two circuits due to exposed wire or maybe they were wired backwards. You'd want to go over the wiring of the 7-way and check for exposed wire or corrosion and fix as needed.
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- Does Reverse Light Circuit on Trailer Wiring Run to Power Wire or Ground Wire on Trailer LightThe reverse light pin on a 7-way (center pin) carries 12 volts of power so it would need to connect to the power wire of the reverse light circuit. The ground of the socket would run back to the ground circuit. Which could either be just the trailer frame or the main ground wire of the trailer.
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- Adapter Recommendation to Convert 4-Way of 2015 Ford F-150 to 7-WayTo convert the 4-way to a 7-way will require the part # 37185. The 4-way would basically just plug into this adapter and you'd have the taillight functions done. If at some point you need to install a brake controller check out the help article I attached on this for more info as well.
view full answer... - Troubleshooting 7-Way Trailer Wiring That Engages Trailer Brakes When Headlights Are Turned OnThe issue you describe, your trailer's electric drum brakes engaging when you turn on the headlights on the tow vehicle, is likely to be a simple mis-wiring of the 7-way. If the trailer connector was very old the issue could be caused by internal corrosion in the connector that could be bridging together two different circuits, but with a brand new 7-way the problem is likely to be either a mis-wired 7-way socket on the vehicle or a mis-wired 7-way plug on the trailer. If you refer to...
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view full answer... - Do Batteries Wired Up In Parallel Need to Use Same Wire GaugeYes, when wiring up a battery bank of parallel batteries wired together you need to use the same gauge wire between the batteries that is used on the current leads for the batteries. Otherwise you aren't getting the full amperage capabilities that two batteries wired in parallel provides.
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Jenny N.
3/2/2023
I recommend using part # 18140 which will zip tie to the hitch. Then you can attach the harness bracket to the end of this bracket.