Troubleshooting No 12V Power on 2017 Unity RV 7-Way
Question:
I purchased a brake kit and light adapter harness. I am pulling with a 2017 Unity RV which is a Mercedes Sprinter 3500 chassis. I am not getting power from the +positive center pin to charge the Jeep Wrangler I am pulling. The rest of the trailer lights work on the jeep through the connector. Does this center pin have a separate fuse located somewhere? All of the fuses check good in both fuse panels. Is there possibly a few inside the 7 pin connector on the RV? Order #114587759 and #114577099 In addition, the trailer light wiring for the Jeep Wrangler for the rear tow hitch does not work properly. When I connected the LED trailer lights to it, tail lights come on, then go out, then 5 seconds or so later come on again for a few seconds. The turn signals will flash once, then stop, then after a few seconds repeat that process. They do not keep pace with the signals on the Jeep.
asked by: Frank A
Expert Reply:
If you have a factory 7-way on your 2017 Unity RV there will be a fuse assuming the 12V power is hooked up. You can check your owner's manual for the fuse location or look on the fuse box lids to identify it. Looking at fuse box diagrams online there are more than 2 locations, but I didn't see anything specifically for towing. There would not be a fuse in the 7-way connector. If the 12V power is not connected you could add a charge line # RM-156-75 to solve the power problem.
I'm not sure what wiring harness you have on your Jeep since it wasn't part of the orders. I'm also not sure if this is a separate problem or if you're trying to triple tow and ran into this. If you're towing a trailer behind your Jeep Wrangler, which is being towed behind the RV, then it sounds like you aren't getting enough power. The trailer wiring connectors would have to be installed before the diodes from your diode wiring kit or there won't be enough power to run the trailer lights.
If you are running into this while driving your Jeep and towing the trailer then the location of the trailer wiring with the diodes won't matter and it is a different issue. I would start by checking the ground connection since that is often the problem when weird things like this happen. You can also check the power on your vehicle connector using a circuit tester like # PTW2993. If you aren't getting power, or it is inconsistent, check your wiring for a short. If this is factory wiring I would check the fuses as well.
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Roadmaster Battery Charge Line Kit for Motorhomes
- Accessories and Parts
- Tow Bar Wiring
- Battery Charge Line Kit
- Roadmaster
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