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 >
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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.