Price: $11.22

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End

Item # PK11720

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Our Price: $11.22

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pollak wiring 7 round heavy-duty 7-pole pin trailer socket - vehicle end
pollak wiring trailer connectors 7 round heavy-duty 7-pole pin socket - vehicle end
pollak wiring vehicle end connector 7 round pk11720
pollak wiring vehicle end connector 7 round
pollak wiring trailer connectors

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pollak wiring trailer connectors 7 round pk11720


  • Trailer Connectors
  • Vehicle End Connector
  • 7 Round
  • Plug Only
  • Pollak
Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact. Lowest Prices for the best wiring from Pollak. Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End part number PK11720 can be ordered online at or call 800-298-8924 for expert service.

Pollak Wiring - PK11720

Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact.


  • Zinc die-cast 7-pole socket connects trailer to towing vehicle
  • Round, floating, solid brass pins
    • Easy alignment and maximum contact
    • Minimum voltage drop is ensured
    • Dielectric (non-conducting) grease coating
      • Protects against corrosion and resistance
    • Wide range of wire gauges acceptable, from #16 wire to #8 ground wire
      • Ground terminal accepts minimum #14 gauge - maximum #8 gauge
      • All other terminals accept minimum #16 gauge - maximum #10 gauge
  • Self-grounding to #1 Ground Terminal
  • Slant-mounted with built-in drain slot on cover
    • Rids housing interior of accumulated moisture
    • Opens and closes with stainless steel spring
    • Bottom lip extended for better plug support
  • 2-Hole mounting style
  • Highest quality - meets and exceeds all standards of SAE J560
  • Interchangeable with all competitive makes


  • Mounting dimensions: 2" diameter hole
  • Volt rating: 6 volts - 28 volts
  • Current rating: 40 continuous-duty amps
  • Wiring configuration:
    • Color - circuit - recommended wire gauge:
      • White - Ground Return - 10 gauge (FMVSS-121 Anti-lock Gauge - 8)
      • Black - Clearance, Side Marker, Identification - 12 gauge
      • Yellow - Left Turn and Hazard Signal - 12 gauge
      • Red - Stop Lamps and Anti-Lock Devices - 10 gauge (FMVSS-121 Anti-lock Gauge 10)
      • Green - Right Turn and Hazard Signal - 12 gauge
      • Brown - Tail, Rear Clearance, Marker and License-Plate Lamps - 12 gauge
      • Blue - Auxiliary Circuit/ABS - 10 gauge
  • 1-Year limited warranty

11-720 Pollak Heavy-Duty, 7-Way, Round Pin Trailer Wiring Socket - Vehicle End
Replaces 52016

Economy - This item

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End
Pollak Wiring

46 reviews

Code: PK11720

In Stock


Our Price: $11.22

  • Wiring
  • Trailer Connectors
  • Vehicle End Connector
  • 7 Round
  • Plug Only
  • Pollak

Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact.

more information →
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Code: HM40920

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  • 4 Flat
  • 7 Blade
  • Hopkins

Quickly and easily replace a damaged 7-way and 4-way, or add a new one to your vehicle with a factory tow package. The twist-in socket has heavy-duty weatherproofing and features a cover that opens 180 degrees.

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Pollak Single-Pole, Round Pin Trailer Wiring Socket - Vehicle End

Pollak Single-Pole, Round Pin Trailer Wiring Socket - Vehicle End
Pollak Wiring

6 reviews

Code: PK11851


Our Price: $24.78

  • 1 Round

Provide power straight from your battery to a variety of auxiliary equipment with this single-pole socket. Socket has a round pin that is removable for easy soldering and a spring-loaded cover to protect interior from the elements.

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Video of Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Pollak Wiring PK11720 Review

Today we'll be reviewing Part # PK11720. This is the Pollak Heavy-Duty, 7 Pole, Round Pin Trailer Wiring Socket. The zinc die cast seven-pole socket connects the trailer to the towed vehicle. It's going to feature the round floating solid brass pins. They're going to provide easy alignment and maximum contact as well as minimum voltage drop.It has the dielectric nonconducting grease coating on all those pins, which is going to protect it against the corrosion, and it's also going to provide rust resistance. A wide range of wiring gauges are acceptable, from 16 gauge wire to 8 gauge ground wire. Ground terminal will accept a minimum of 14 gauge with a maximum of 8 gauge, and all other terminals accept a minimum of 16 gauge with a maximum of 10 gauge. When mounted, it's got a nice slant design, so water's going to run off.

It's going to prevent moisture from building up, especially inside the connection points. It's got the nice stainless steel spring lid that's going to open and close very easily. It's also got the bottom lip that's going to extend for better plug support. It's got the two-hole mounting design. The distance from the center of one hole to the center of the other is going to measure 3", and those holes are going to measure 1/2" by 3/8 of an inch. This plug is going to be interchangeable with all competitive makes.

It's going to require a 2" hole diameter for correct mounting. It's going to give us a volt rating of 6 to 28 volts with a current rating of 40 continuous duty amps. The wiring configuration. The white wire's going to be for a ground. We recommend 10 gauge for that. Black is going to be for clearance, side marker, and identification. Lights.

The yellow is going to be for left turn and hazard signal. We recommend 12 gauge for both. Red is going to for stop lamps and anti-lock devices. We recommend 10 gauge wiring. Green is going to be for right turn and hazard signal, and brown is going to be for your tail rear clearance marker and license plates lamps.

We recommend 12 gauge for both of those, and then blue is going to be for your auxiliary circuit, and we recommend 10 gauge wiring. That's going to do it for our review of Part # Pk11720. This is the Pollack Heavy-Duty, 7 Pole, Round Pin Trailer Wiring Socket. .

Customer Reviews

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End - PK11720

Average Customer Rating:  4.9 out of 5 stars   (46 Customer Reviews)

Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact.

- PK11720

by: Ian H.06/15/2015

Excellent product! - have, over only a few years, steadily worked my way through progressively more durable trailer cable sockets. The last one was the Hopkins heavy-duty, or something to that effect. The plastic casing on it broke within three months. I'm really looking forward to putting these to the test - I'm a farrier - I pull a trailer every day; the traffic in this area means that I must rely on excellent contact between vehicle/trailer for turn / brake signals and functioning trailer brakes. Nothing less. These sockets are heavy, all-metal (zinc-coated - road salt shouldn't be a problem), with few / no seams. When the trailer end is plugged into the truck receiver - it's a nice tight fit, with no movement: it's locked in. There are only two drawbacks for the homeowner who is looking for the do-it-yourself package: if you are looking for a metal bracket that bolts underneath the truck bumper and holds this part - there isn't any. And no bolts, either. I don't know if they sell them for these - I didn't check. I simply manufactured my own. So far, I'm delighted with the product. 203673

- PK11720

by: Sartor07/10/2017

I ordered the 7 pole socket (PK11720) and the rubber boot for it. (PK11761) Also a trailer end plug (PK11700) to fit into the socket. The items arrived on the exact estimated arrival date that I was given on the day of ordering. Wiring the plug and the socket was very easy. Each terminal has a small screw that holds the end of the wire in place. It is a simple matter of threading the screw out, putting the wire in the hole, and then tightening the screw onto the wire. The boot fits snugly onto the back of the socket. I used these parts to repair the power cable assembly to a truck mounted forklift. The parts are exactly what was needed to replace what had been damaged. The quality is good and the prices are excellent. I will use in the future when I need related items. I am very pleased. 403804

- PK11720

by: John G01/02/2016

This is much better than the OEM on my New Holland Tractor asit is made of metal. It also cost less than the all plastic replacement from the dealership. etrailer was fast with delivery. Thank you. 234645


It is working out very nicely, really glad I bought it!

John G - 01/05/2017


- PK11720

by: Mike M.10/13/2015

Quality product arrived on time. Will make future purchases with 229902


Performed as expected to date.

Mike M - 10/12/2016


- PK11720

by: DW08/12/2014

Bought to replace a 12 year old Pollak identical connector that I removed and could not re-use due to wire connections on the back being corroded (road salt area). The 12 year old connector worked fine except the flip up cover was a bit stiff. The 12 year old connector was also made in USA. The new connector I just received is made in China. From the price, I had hoped it was still made in USA. It seems that most of the time I am disappointed with the newer imported China versions of products once manufactured in USA. So my expectations for this product to have a long life are not very high. 146341

- PK11720

by: Levi F.03/24/2017

Excellent product! I bought this to replace the old, brittle, and broken plastic trailer connector on my 1973 aluminum camper. The plastic one stood out against the aluminum which I didn't like. So, I'm excited how this will blend in and look more natural. Besides aesthetics, this very sturdy and ruggedly built. It will clearly outlast the camper, no doubt. Will definitely buy again if I find myself with a different camper in the future. 358289

- PK11720

by: Lee S04/26/2014

I would highly recommend this. It is heavy duty and quality built. A great value for the money 127497

- PK11720

by: Marcelo P.07/23/2015

The metal body and good quality pins and connections make this one the only one for a professional job. Remember if you use dielectric grease and the rubber boot you'll never have corrosion in your connections . Dissimilar metals and weather are a bad combination. 213712

- PK11720

by: Toby N.06/09/2016

Awesome product selections and quick response towards shipping. Made me feel like I was actually getting somewhere. If you have a trailer, camper, or any type of tow behind application get HOOKED UP with this company. Very satisfied 259480


I hook and unhook my trailer about twice a day as I need my truck for hauling stone and dirt. I have put this through the ringer. Still good as new...Happy customer

Toby N - 06/09/2017


- PK11720

by: Tom11/16/2017

I could not find this style or make trailer plug in my local auto parts store. I got tired of trying to find it so I ordered it on line. etrailer was convenient and less expensive than any other website. 452467

- PK11720

by: Matt07/07/2014

Great construction of the product, durable enough to withstand harsh working conditions and "operators" I am using that term lightly due to the mishaps that occur on a regular basis at my location. 139763

- PK11720

by: charlie johnson08/26/2013

as i have order several things on this order i have not used this device yet.i looked it over and i am completely satisfied. quality ,price and extra fast shipping. 96986

- PK11720

by: JohnG10/31/2016

Thank you guys, Order was delivered very quickly, the price was very reasonable. I cant describe how happy I am with ETrailer . Thanks again, John 312571

- PK11720

by: Ken03/08/2013

Great, Fast, Knowledgable and Polite Service. Return policy is also terrific no questions asked. I will use e trailer again. Thank You Ken 69618

- PK11720

by: RJ07/23/2015

This connector is really nice and with the screw tightening wire connections that are on it, it will make the wiring a lot easier to do. 213933

- PK11720

by: Michelle03/28/2017

I got my parts in a timely manner and already have them installed. The quality is first class and the fit is perfect. 359669

- PK11720

by: Robert B02/23/2017

Great service and product was high quality. No junk and have to say product exceeded my expectations. Thank you 347383

- PK11720

by: Jim B09/07/2017

Worked like a charm. Had a mishap with items ordered vs items shipped, but they fixed it quick. Great company! 429767

- PK11720

by: Buck W03/04/2014

This item worked well for my application. It is bigger than I expected but I'm anticipating good performance! 118398

- PK11720

by: Kevin01/16/2015

I like your web site ! I like ordering from etrailer ! Easy, Fast, and dependable ! Very good prices !!! 169132

- PK11720

by: Tish06/21/2017

Excellent service and fast delivery. I would definitely recommend doing business with this company. 396984

- PK11720

by: Farmer Rob06/11/2017

Did what it was supposed to do. Well made, and easy to hook in to wiring. Should last a long time. 391921

- PK11720

by: carmon titus03/13/2015

Looks good ,will be a few days before it is used,waiting on the other parts to complete install. 178239

- PK11720

by: Al B.10/07/2015

Extremely well made and very solid. I selected it because it can accept larger wire sizes. 229444

- PK11720

by: Bob J.09/02/2016

Very fast service AGAIN! Always my first choice when shopping for trailer parts. 290706

- PK11720

by: jerry s11/19/2014

always get good products and service and ya'll always have the items i need 161887

- PK11720

by: fortin racing03/23/2017

great replacement for one that we broke. still going strong 357554

- PK11720

by: Adam C12/25/2015

Works great and came faster than I thought it would! 234278

- PK11720

by: Anthony10/04/2016

Perfect product. Would come back to you guys again 303137

- PK11720

by: Blake H.07/06/2016

Excellent product. Very heavy duty/well designed. 268646

- PK11720

by: Dean05/28/2016

No problems, smooth transaction. Easy install. 252798

- PK11720

by: Justin07/08/2014

Well-made product and fast shipping. T hanks. 139978

- PK11720

by: Jeff W.11/17/2016

Excellent quality at a reasonable price. 317459


As far as I know fine. It was part of a test fixture for a student project.The company was impressed with the fixture, and took it with them.

Jeff W - 11/17/2017


- PK11720

by: Evan02/07/2013

Hi quality, perfect for my application 65259

- PK11720

by: Josh H07/12/2016

Exactly what I thought I was buying 271012

- PK11720

by: Semperfiservices04/26/2017

Still works great a year later! 372511

- PK11720

by: LuisP04/24/2017

Great product and built strong! 371843

- PK11720

by: Ted L.10/18/2016

All these products were great. 309399

- PK11720

by: Joe S.04/09/2015

Received both parts very fast. 184210

- PK11720

by: Anthony10/27/2017

looks good I would buy again 446765

- PK11720

by: Harry W12/02/2011

great item and fast delivery 27532

- PK11720

by: Bubba U09/30/2017

Work great thanks. 438101

- PK11720

by: Dave S09/25/2016

Easy to install. 299741

- PK11720

by: Dimitri05/13/2016

Great product!!! 250154

- PK11720

by: Mike from NC10/09/2017

Great Product 440871

- PK11720

by: elisa07/27/2017

ok 413012


Ask the Experts about this Pollak Wiring
Do you have a question about this Wiring?

  • Can I Tow a 5th Wheel Travel Trailer with a Semi Truck or 18-Wheeler
  • The king pin dimensions are the same between fifth wheel trailers and large commercial trailers. Both types of trailers use a standard 2 inch king pin. Semi trucks were not technically designed to tow camping style fifth wheel trailers, so there are several factors that you will want to take into consideration before attempting to tow. First, you will want to make sure the truck can tow the trailer level. Towing the trailer with the nose too high or too low can cause issues with sway,...
    view full answer...

  • Wiring Diagram for 7-Way Round Pin Trailer and Vehicle Side Connectors
  • I have added a photo detailing the wiring connections for the Pollack Heavy-Duty, 7-Pole, Round Pin conncetor, # PK11700, see link. This is a SAE J560 compliant connector. The wiring diagram for the vehicle side connector, # PK11720, is pictured also.
    view full answer...

  • Wiring Diagram for a 1997 Peterbilt Semi Tractor with 7-Pin Round Connector
  • The wiring color codes and wire gauge recommendations for the Pollak Heavy-Duty, 7-Pole, Round Pin, Trailer Wiring Connector, item # PK11700, are listed below. White - Ground Return - 8 gauge Black - Clearance, Side Marker, Identification - 12 gauge Yellow - Left Turn and Hazard Signal - 12 gauge Red - Stop Lamps and Anti-Lock Devices - 10 gauge Green - Right Turn and Hazard Signal - 12 gauge Brown - Tail, Rear Clearance, Marker and License-Plate Lamps - 12 gauge Blue - Auxiliary...
    view full answer...

  • Towing a Trailer with Electric Brakes with a Semi Tractor with Air Brakes
  • To tow your trailer that uses an RV style 7-way blade style connector with your semi that has a 7-pin connector, you need to construct an adapter that will also combine the brake signal into the right and left directional signal pins. This can be done by using a female 7-pin socket # PK11720 to accept the plug from the semi, a tail light converter # 119178 and a female 7-way RV blade-style socket # PK12-707E. The converter would be wired in between both sockets to combine the brake...
    view full answer...

  • Pin-Out Wiring Diagram for a Trailer Side and Vehicle Side 7-Way Blade Style Trailer Connector
  • I can certainly help you out. First, I have included a link to our wiring FAQ article that shows how to wire both the vehicle side and trailer side connectors. The section you need is about in the center of the article and says 7 Way Trailer Connector followed by 7 Way Vehicle Connector. I will also give you a quick explanation below. When looking at the back of the TRAILER SIDE connector where the wires attach: 1 oclock position (pin 4) = 12 volt battery power 3 oclock position...
    view full answer...

  • Recommended 7-Way Round Trailer Connector And Wiring
  • If you are looking for a round connector with a 7-way blade I recommend part # H20046. This is a trailer end connector with 8 ft molded wire. For a 7-way with 6 ft of molded wire you need part # H20044, and for the connector with 4 ft of molded wiring you need part # H20043. for a connector with a coiled wire I recommend the WesBarg 7-Way, RV-Style Connector, part # WG54006-043. This has 6 ft of coiled wire attached. If you are looking for a 7-way with round pins we do not offer a 7-way...
    view full answer...

  • Wiring Diagrams for 7-Way Round Trailer Connectors
  • I attached a diagram that shows how most 7-way rounds like the # PK11720 that you referenced will get wired up. As long as you got yours wired up correctly and your trailer taillights and brakes are functioning correctly that's all that should matter, but occasionally there are some trailers that end up wired slightly different than others so the diagrams we offer don't match up perfectly. In those cases you have to wire up everything by function so that everything matches up properly....
    view full answer...

  • How to Make a 5-Way Round Pin to 7-Way Round Pin Trailer Connector Adapter
  • A 5-Way Round to 7-Way Round trailer adapter is not available, but I can tell you how to make one and what you will need. If the 5-Way round is on the vehicle, you will need the following: 5-Pole, Round Pin Trailer Wiring Connector, # PK11501 7-Pole, Round Pin Trailer Wiring Socket, # PK11720 7-Pole Rubber Socket Boot, # PK11761 Jacketed 6 Wire - per foot, # DW04906-1 (get 2 feet worth) Start by testing the functions of the 5-Way with a circuit tester, # 3808 if needed. Once...
    view full answer...

  • How to Wire the Pollak 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End # PK11720
  • On the back of the Pollak 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End, part # PK11720, it is marked alongside the pin with the color of the wire that connects to that pin location. I am also including a photo that will show a 7-Way round pin connector for the vehicle end with the colors and functions listed for each pin. I am also including a link to a FAQ page on trailer wiring.
    view full answer...

  • What Wire Color Codes and Functions Are Used for Pollak Connecter 12-705 and PK11720
  • There is no industry standard wiring code. Pollak uses the following: White - Ground Return Black - Clearance, Side Marker, Identification Yellow - Left Turn and Hazard Signal Red - Stop Lamps and Anti-Lock Devices Green - Right Turn and Hazard Signal Brown - Tail, Rear Clearance, Marker and License-Plate Lamps Blue - Auxiliary Circuit/ABS We have a different combination of colors we use for specific functions which you can see in the wiring FAQ article that I have linked. Finally,...
    view full answer...

  • 7-Way RV and 7-Way Round Pin Brake Controller Output Wire Connection Location.
  • The blue electric brake power feed wire should be connected to the terminal in a 7-Way RV style connector, at the 7 o-clock position when looking at the inside of the connector. If looking at the outside of the connector the terminal is in the 5 o-clock position. If the connector you are speaking about is a 7-Way round pin connector, the blue wire will be connected at the center position when looking at the inside or outside of the connector. I have linked a photo of each of these...
    view full answer...

  • Parts Needed to Add a 7-Way Trailer Connector and Brake Controller to a 1972 Chevrolet Pickup
  • We have everything that you will need to add a 7-way trailer connector and a brake controller for trailer brakes to your 1972 Chevrolet pickup. You will need a 4-Way Wiring Kit, # 18252, the 7-way and 4-way Installation Kit, # ETBC7, and a brake controller, I recommend the Prodigy P2, # 90885. The first thing to do is to install the 4-way wiring kit, # 18252. This kit includes a wiring harness with a 4-flat trailer connector, a circuit tester and 4 quick splices. To install this wiring...
    view full answer...

  • Converting an Existing 9-pole Trailer Connection Plug to a 7-Way Connection
  • We do not supply a 9-pole to a 7-blade connector converter, but you can definitely convert your existing trailer connector to a 7-way blade connecter that will work with your truck. To do this you will need a replacement 7-blade connector like # PK12706. You will then disassemble the existing trailer connector and install the 7-way blade style connector. When you take apart the 9-pole connection point the functions should be labeled, and you will want to match up functions to the 7-way...
    view full answer...

  • Wiring Adapter Needed for Towing 5th Wheel Trailers with a Kenworth Tow Truck
  • We have the items you need to make an adapter to go from the connector on your Kenworth tow truck to the plug on the fifth-wheel trailers you will be towing, but there is not a pre-made adapter available. There are several situations depending of which trailer connectors you need to adapt to,so I will list the parts for each. First, if you need to go from a round pin connector, like # PK11720 on your tow truck to a 7-Way RV style trailer connector, like # PK12706, on a fifth-wheel RV...
    view full answer...

  • Is it Better to Switch to a 7-Way Blade Style Trailer Connector Over a 7-Way Round Pin
  • The 7-Way blade style trailer connector is the most common 7-Way in use at this time. It would be beneficial to switch to this style. However, if you already have a 7-Way round connector you can just use an adapter to go to a 7-Way blade style when needed. You can use # PK12-724. If you want to go ahead and switch from the 7-Way round to the blade style I recommend a multi-tow connector, # HM48470, which has a 7-Way blade style, a 5-Way flat, and 4-Way flat. All you will need to do is...
    view full answer...

  • How To Find Cold Side Of Stop Light Switch On Vehicle For Brake Controller Installation
  • Normally you can find the brake light switch under the dashboard at the top of the brake pedal. There could be a number of wires attached to the switch so you can use a tester like part # 3808 to test the wires. Since the auto manufacturers can use different color wires it is always best to use a tester and check the wires for function and not color. You would need to find the wire that only shows power when the brake pedal is pressed. That would be the wore that gets attached to the...
    view full answer...

  • Agricultural Type 7-Way Vehicle Socket for Trailers Using Round-Pin 7-Way Plugs
  • 7-way trailer connectors can be wired in several ways and heavy-duty commercial/agricultural round-pin 7-way wiring can be different too. Please refer to the linked image to see the different vehicle-side connectors and their common wiring configurations. To use your trailers that have plugs like # PK11702 with your F-250 you will need to install a socket such as # PK11720. A circuit tester like # 3808 will help you identify the function on each wire of the truck's existing 7-way. The...
    view full answer...

  • Trailer Tail Lights Go Out With Headlights On And When Brake Pedal is Pressed On 1993 Chevy 3500
  • It sounds like you have a ground problem on the trailer. However, there also could be a problem on your tow vehicle. We can isolate the problem to narrow the search a bit. Disconnect the trailer from the truck. Using a circuit tester, like part # 3808, test the 4-Way connector. Clip the tester to the truck frame as your ground, and test the brown, yellow and green wires to make sure they function properly. Brown is tail lights, yellow is left turn and brake, and green is right turn and...
    view full answer...

  • Troubleshooting a Pollak 7 Way Vehicle Connector Plug Wiring Malfunction
  • I agree it sounds like there is a wiring issue, and to get the functions to work properly you will have to re-wire the vehicle connector. Please keep in mind that you do not want to rely on color alone to diagnose the wiring functions, it is always recommended to test and verify function of the wire. You will need a circuit tester like the Quickee # 3808 to verify these functions. I have included a helpful article that shows typical wiring for both the trailer and vehicle connectors....
    view full answer...

  • Installing 7-Way Trailer Connector and Brake Controller On 2003 Chevy Blazer
  • To install a 7-Way blade style RV connector and brake controller on your 2003 Chevrolet Blazer, you will need to install the Brake Controller 7 and 4 Way Installation Kit, part # ETBC7. To begin, since there is not a factory 4-way on your truck, you will want to just cut the 4-way connector off that is connected to part # ETBC7. Those wires will need to be spliced into the correct wires on your vehicle, you will want to use a circuit tester, part # 3808 to test functions of the wires....
    view full answer...

  • No Brake Signal on a 7-Way Round Pole Trailer Connector on an RV r
  • If your RV came with a 7-Way round pole trailer connector then it could be that there are fuses or relays that need to be in place or replaced if present to make the 7-Way fully functional. Check the owners manual to determine the location of any fuses or relays related to the trailer connector. If you hardwired in the trailer connector and the RV has separate turn and brake lights then the brake circuit will not be present with the turn signals on the 7-Way. You would need to covert...
    view full answer...

  • Pollak 7-Way Round to 7-Way Flat Adapter Recommendation
  • If your vehicle has a 7-way round connector like a Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket # PK11720 then you could use a Pollak Trailer Connector Adapter # PK12-724 to allow you to tow a trailer with a flat 7-way connector. I also attached an FAQ article on wiring for you to check out also. I would recommend you test the 7-way on your semi and determine if the 7-way has separate or combined tail light circuits. If you have separate circuits on the trailer connector...
    view full answer...

  • Troubleshooting No Trailer Running Lights on a 2008 Nissan Frontier
  • If the harness you installed is aftermarket and not from the factory, then the taillights will not work unless you have a factory tow package. If you do not have a factory tow package, you can use a different harness, # 119179KIT. I have included installation details and an installation video below. I checked a colleagues truck, he has a 2004 model, so there may be some differences. But, there are some fuses under your hood, passenger side, that may say something like HD tail light....
    view full answer...

  • Towing Trailer with 4-Pole Connector with 2001 Land Rover Discovery with 7-Way
  • If your Discover has the 7-way connector that uses the round pins like part # PK11720, we do not offer a pre-made adapter, but one can be easily constructed using a 4-pole vehicle end connector like part # 18002 and a 7-way round pin trailer end connector, part # PK11700. The 4-pole would be wired to the 7-way round pin as shown in the diagram I made for you. If your Discovery has the 7-way with the blade-style pins like part # PK11893, an adapter is available, part # HM47365.
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Info for this part was:

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