Adding a 7-Way to Bumper and Bed of a 2012 Ram 2500 that Originally Came with a 7-Way
Question:
i have a 2012 ram 2500. when i bought it the factory 7 pin trailer plug located in the rear bumper was missing and one was installed in the bed for a gooseneck. the wires to the plug are different colors and spliced in to the factory wiring. long story short it was done incorrectly. i want to leave the bed plug and added a plug back in the bumper but i cant seem to figure what color wires are what, even after disconnecting them and testing each one with a multi-meter, i cant figure it out. if anyone can help me that would be great. the factory wires at the harness tail are as follows: green brown black white/orange stripe white/blue stripe black/gray stripe red/purple stripe white/green stripe
asked by: Brandon S
Expert Reply:
Usually when there is a question on the function of a wire the solution is to test that wire. But you indicated that you have tested the wires and still cannot figure out the functions. But you didn't say why that is. Were you getting conflicting readings from the meter? A meter might be a little too sensitive for this test. Really all that is needed is a circuit tester such as # PTW2993.
Two of the wires will show power when the brake pedal is pressed. And one of those wires will also have power with the left turn signal while the other will have power with the right turn signal. Another wire will have constant power. This is the 12-volt circuit. One wire will have power when the truck running lights are on so it is the running light wire.
One wire may have power when the truck is in reverse. One will only have power if a brake controller is activated. And the last wire is the ground. That should help to narrow things down some.
Take a look at the picture I have included that shows the functions of a vehicle side 7-Way connector. Ignore the colors and just focus on the positions of the functions. that will help out quite a bit since I can't tell you what the functions of the wires you have are.
Another way to go about this is to completely remove that in-bed harness and the wires spliced in. There should be a harness with a rectangle connector under the truck that the original factory 7-Way at the rear plugged into. To replace the connector at the rear of the truck you would just need # HM40975-11933.
Then to add a 7-Way back to the truck bed you can use # 41157 which will plug in line with # HM40975-11933.

Products Referenced in This Question
Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug
- Custom Fit Vehicle Wiring
- Fifth Wheel and Gooseneck Wiring
- 10 Feet Long
- Custom Fit
- 7 Round - Blade
- Hopkins
more information >
7- and 4-Pole Trailer Connector Socket w/ Mounting Bracket, Chrysler/Dodge OEM Plug Adapter
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- Custom Fit
- 4 Flat
- 7 Round - Blade
- Pollak
more information >
Product Page this Question was Asked From
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- Custom Fit
- 4 Flat
- Tekonsha
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Trailer Wiring
- Shop: T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Shop: Trailer Hitch
- Q&A: 7- to 4-Way Adapter for a 2016 Chevy Suburban with Factory 7-Way Trailer Connector
- Q&A: Will Tow Ready T-One Connector with 4-Pole Connector Fit 2008 Chevrolet Silverado
- Q&A: Will Plugging in a Rampage LED Light Bar Disable Backup Sensors on a 2009 Chevy Suburban
- Shop: Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug
- Shop: TorkLift Camper Tie-Downs - Custom Frame Mount - Front
- Search Results: 7way
- Search Results: 7 pin
- Search Results: 7 way splitter
- Search Results: r3500
- Shop: TorkLift Camper Tie-Downs - Custom Frame Mount - Rear
- Article: How to Mount a Truck Bed Camper
- Article: 5th Wheel Hitch Installation | The Ultimate DIY Guide
- Q&A: Can a 5th Wheel Trailer be Towed with a Slider Hitch in the Slid Back Position
- Shop: B&W Patriot 5th Wheel Trailer Hitch w/ Slider - Dual Jaw - 18,000 lbs
- Video: Hands-On with the 5th Airborne Custom Wedge for B&W Fifth Wheels
- Shop: Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 7-Pole Connector and Cover Plate - 7' Long
- Shop: Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 4-Way and 7-Pole Connector - 7' Long
- Search Results: reese sidewinder
- Q&A: Replacement Exterior Shower Parts for 2013 Arctic Fox 811 Truck Bed Camper
- Q&A: Installation Measurements For Reese 5th Wheel For Dodge Ram Pickup Short Bed
- Q&A: How To Determine The Correct 5th Wheel Hitch Height For A 2021 Ram 2500 And Grand Design 29R
- Search Results: a7311
- Search Results: a7200
- Shop: Suspension Enhancement
- Video: Hopkins Endurance Fifth Wheel Wiring Harness Installation - 2012 Ram 3500
- Video: Hopkins Custom Fit Vehicle Wiring - Fifth Wheel and Gooseneck Wiring - 41157 Review
- Video: EZ Connector Custom Fit Vehicle Wiring - Fifth Wheel and Gooseneck Wiring - 319-S7-09 Review