Troubleshooting Hyper Flashing Trailer Lights on Mercedes-Benz Sprinter Van
Question:
I have 2017 Sprinter. When hooked up to my new boat I experience the same flashing that has been reported by others. I bought your 7 to 7 adapter and it doesn’t solve the problem despite what your expert reports. Have you got another solution? My rig has been at the local MB dealer for 3 weeks and the can’t resolve it!
asked by: Warren
Helpful Expert Reply:
The hyper flashing due to LED lights on your trailer is often solved with the 7-way adapter you mentioned the Trailer Connector Adapter w/ Lamp-Out Sensor Bypass - 7-Way RV to 7-Way RV - Vehicle End # 20142. The issue is often that LED's pull so much less power that the computer systems don't know how to accommodate the small electrical load.
What I recommend doing next is checking each ground connection to ensure you have a bare metal to metal connection. Then if you still have issues, I recommend using the Diamond LED Light Bulb Load-Resistors # DI34ZR. You will want to make sure you install them properly, so I've attached a photo to assist.

Products Referenced in This Question
Trailer Connector Adapter w/ Lamp-Out Sensor Bypass - 7-Way RV to 7-Way RV - Vehicle End
- Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 7 Round - Blade
- Plug Only
- 7 Round - Blade
- Tow Ready
more information >
Product Page this Question was Asked From
Load Resistor Kit for LED Turn Signals - 50 Watts - 6 Ohm - Qty 2
- Accessories and Parts
- Trailer Lights
- Load-Resistor Kit
- Diamond
more information >
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Rich P.
4/6/2020
I was troubleshooting blinking running lights on a trailer with 100 incandescent bulbs hooked up to a MB Sprinter. Trailer had 12 running lights, 2 brake/turn signals. 1.7 ohms on running light .7 ohms on turn/brakes circuits. I tried the 7 to 7 pin adapter, no worky worky I felt I needed to bring the resistance down closer to the working .7ohm threshold of turn/brake circuits. So I replaced 6 of the 12 incandescents on running lights with LEDs. Boom! Fixed. I dont know about the pule the Sprinter sends, but I felt I had to get the resistance more inline with what was there. I was correct. Problem is 100 resolved.