Troubleshooting Trailer Lights Not Working with Hopkins 4-Way/7-Way Adapter on 2006 Toyota Sienna
Question:
Thanks Jon. I figured out the issue. When I test testing the Hopkins adapter while touching the disconnected ground wire and the blade where I was expecting power I was seeing no power. However once I put the Hopkins ground wire on the van again and tested the same blade I had power. So why weren't my trailer lights working? Well eventually I got them all working. I had to unplug and replug the trailer to the Hopkins adapter several times. The result I believe was knocking some grime off of the camper plug and finally getting good contacts all the way through. It didn't look especially dirty, but I believe that was the only problem in my initial setup. Thanks again. If there's a way for me to share this conclusion in the online answer page you set up, please let me know.
asked by: Chris
Expert Reply:
It is always a possibility that an adapter being used is bad but since you are only testing your trailer lights when you're using the Hopkins Adapter # 37185 I recommend making sure the ground on the Hopkins is connected to a clean, bare-metal surface and testing the wiring on your trailer, especially since the Curt T-Connector # C55580 is working properly on your 2006 Toyota Sienna.
If your ground is connected to a clean, bare-metal surface then what you need to do is either connect the trailer to another vehicle with a 7-way that is known to work or take a 12V battery, like what's in your Sienna, and use the positive terminal to test the different pins on the 7-Way (after grounding the negative terminal). I have attached a photo showing which pins should carry which functions on your trailer for you to reference. It would also be helpful to ensure your trailer 7-Way is clean and free of debris and that all of your light grounds on your trailer are connected to clean, bare-metal surfaces as well.
Should you still have issues after all of this then we can likely say that the adapter is bad and needs to be replaced.
Products Referenced in This Question
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Converter
- Custom Fit
- 4 Flat
- CURT
more information >
Product Page this Question was Asked From
Adapter 4-Pole to 7-Pole and 4-Pole
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 4 Flat
- Plug and Lead
- 4 Flat
- 7 Round - Blade
- Hopkins
more information >
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on Trailer Wiring
Chris
7/1/2019
Thanks Jon. I figured out the issue. When I test testing the Hopkins adapter while touching the disconnected ground wire and the blade where I was expecting power I was seeing no power. However once I put the Hopkins ground wire on the van again and tested the same blade I had power. So why weren't my trailer lights working? Well eventually I got them all working. I had to unplug and replug the trailer to the Hopkins adapter several times. The result I believe was knocking some grime off of the camper plug and finally getting good contacts all the way through. It didn't look especially dirty, but I believe that was the only problem in my initial setup. Thanks again. If there's a way for me to share this conclusion in the online answer page you set up, please let me know.