Will Turn Signal from Motorhome Activate Turn Signal on 2016 Smart Fortwo With Diode Kit
Updated 10/02/2025 | Published 09/29/2025
Question:
I installed this to 2016 Smart Fortwo and also the 4-diode wiring harness RM-152-1676-7. I followed the instructions and video for older Fortwo model, which user alternative wiring for indicator light from the kill switch instead from brake signal. Now the system activates when I use the turning light signal is on my RV... this cannot be right, right?
asked by: Henri A
Expert Reply:
Hi Henri; I'm not entirely sure I understand what the problem is. What system is activating when you use the turn signal on your RV? The Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles # RM-152-1676-7 should carry the tail, brake, and turn signals from your RV to your Smart Fortwo. If the turn signal on your RV is activating the turn signal on your towed vehicle that is expected.
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Product Page this Question was Asked From
Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Hybrid Adapter Cord
- Flat Tow Wiring Harness
- Splices into Vehicle Wiring
- Diode Kit
- Universal Fit
- 7 Blade to 6 Round
- Roadmaster
more information >
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on Flat Tow Wiring Harness
Henri A.
10/1/2025
Sorry Robin, I think context of my question was lost somehow when I navigated on the site. I thought it got linked to product page I was looking at, clearly it didn't. My question was related to Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional (SM99251) and 4-diode wiring co-operation. I thought there is something wrong in C453 wiring, which is causing brake module to activate on turn signal. After reading through the instructions again, I think I skipped somehow the finetuning part and my G-force sensor and it's currently set at full sensitivity, which is causing my issue. I'll conduct adjustments tomorrow per instructions :D