Not All Boat Trailer Lights Light Up Using a 7-Way to 5-Way Adapter On a 2013 GMC Sierra
Question:
I have a 2013 GMC sierra with a round 7 pin connector. I want it to fit a boat trailer wiring adapter with a 5 connection flat end. I have already purchased one that doesnt work, not all the trailer lights work. The trailer has a white wire to control the silenoid when put in reverse. So, how do I know the part #HM47025 will be any different?
asked by: Patrick Q
Helpful Expert Reply:
Since your truck is new, it is not likely that there is a problem with its wiring. So the adapter you already have could be faulty or there is a ground issue on the trailer. The functions of a 5-Way are as follows:
The covered pin is ground. Next to it is the running light pin, followed by the left turn/brake light pin, then the right turn/brake light pin. And at the very end there is the pin for the electric reverse lockout solenoid on your surge coupler. Make sure that your 5-Way on the trailer is wired this way.
If that is how it is wired then there could be a problem with the adapter you have. Plug it into the truck and use a circuit tester like # PTW2979 if you do not already have one to test the 5-Way end of the adapter. Have someone sit in the truck and run through the functions while you test. If the adapter shows all the proper signals then the problem is on the trailer. If the pins do not show the proper signals, unplug it and make sure all of the pins on the truck 7-Way work.
If the 7-Way functions normally then the adapter is faulty and needs to be replaced. If the 7-Way is not working properly then there is something wrong with the tow package wiring on the truck and, since its new, the dealer can probably take care of that as a warranty issue.
If both the 7-Way and adapter check out fine then the issue is on the trailer. Most likely there is a bad ground. Start by making sure the main trailer connector ground is attached to a clean and corrosion free bare metal surface. Then do the same with the lights. If your trailer has an aluminum frame or folding tongue you will need to run jumper ground wires from the lights to the main trailer connector ground.
Products Referenced in This Question
Product Page this Question was Asked From
Hopkins Heavy-Duty Trailer Coiled Wire Adapter 7-Way to 5-Way Flat with Nite-Glow
- Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 0 - 5 Feet Long
- 7 Round - Blade
- Plug and Lead
- 4 Flat
- 5 Flat
- Hopkins
more information >
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