Does TowSmart 7-Way Replacement TS37QR Require Factory Wiring
Updated 01/27/2026 | Published 01/14/2026
Question:
Will this product tie into the factory wiring harness with no existing tow package?
asked by: Brian
0
Expert Reply:
Hey Brian, if your 2015 Mercedes-Benz M-Class doesn't have factory wiring then the TowSmart harness part # TS37QR wouldn't work. I would recommend checking the rear of your vehicle to see if you can find the square plug this is designed for and go from there. Let me know what you find (if anything) and we can go from there to find what would be best way to have a trailer wiring connector installed.
expert reply by:
Jameson C
0
Product Page this Question was Asked From
TowSmart Replacement Custom Multi-Tow 7-Way and 4-Way Trailer Connectors
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Tow Package
- 4 Flat
- 7 Blade
- Plug and Lead
- TowSmart
more information >
Continue Researching
- Q&A: Parts Needed To Tow Airstream Caravel FB22 With 2013 Mercedes ML350
- Search Results: aluminum ball mount
- Search Results: fulton
- Search Results: trailer hitch ball mount
- Search Results: trailer hitch
- Search Results: hitch pin
- Video: Review of TowSmart Custom Fit Vehicle Wiring - Trailer Hitch Wiring - TS37QR
- Shop: Trailer Wiring
- Shop: Trailer Hitch
- Shop: TowSmart Replacement Custom Multi-Tow 7-Way and 4-Way Trailer Connectors
- Video: Comprehensive Review: Curt Ball Mount for 2" Hitches
- Shop: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Shop: Weigh Safe Ball Mount w/ Built-In Scale for 2" Hitches - 2" Drop - 10,000 lbs - Aluminum
- Shop: Curt Trailer Hitch Receiver - Custom Fit - Class III - 2"
- Shop: Curt Ball Mount for 2" Hitches - 3" Rise, 4" Drop - 8,000 lbs - Aluminum
- Shop: Curt Ball Mount for 2" Hitches - 1" Rise, 2" Drop - 8,000 lbs - Aluminum
- Shop: 2" Hitch Ball - 1" Diameter x 2-1/8" Long Shank - Stainless - 7.5K
- Q&A: Wiring Installation Instructions for Hopkins LED-Compatible Tail Light Converter # HM48895
- Q&A: How to Wire in a Hopkins Tail Light Converter Kit # HM48895 to a Can Am Spider
- Q&A: How To Wire the Hopkins Tail Light Converter Kit with 4-Way Flat Connector HM48895
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Video: The Low-Down on the Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Article: Trailer Wiring Diagrams
- Search Results: trailer wiring
- Video: Curt T-Connector Vehicle Wiring Harness Review C56040
- Article: How to Choose the Right Trailer Hitch Class
- Search Results: trailer tires and wheels
- Video: Curt Powered Tail Light Converter Installation - 2023 Kia Telluride
Explore Expert Info
![Our Expert]()
on Custom Fit Vehicle Wiring
on Custom Fit Vehicle Wiring
Jameson C.
1/27/2026
Hey Brian, what did you find when you checked the rear of your M-Class for that square plug? Once you know what’s back there, we can figure out the best way to get your trailer wiring connector set up.