What Pin On My 7-Way Should Be Hot All The Time?  

Question:

Expert Reply:

Hello Otto. The 12v pin on your 7-way should be hot all the time, assuming it is wired directly to the vehicles battery. This would generally be the 1 o'clock pin. I have included the wiring diagram for a 7-way below for your reference. I am not quite sure what you mean by "tm pin" though so if you can provide more information, I am happy to provide you with a more detailed answer.

expert reply by: Jesse M

0

7 way diagram
(click to enlarge)

Otto B.

4/23/2024

My tail & running light pin is hot all the time, even with key off.

Jesse M.

4/23/2024

@OttoB The running light and tail light pins should not be active while the vehicle is off. The cause could be a defective converter box, or damaged wires/ a short.

Otto B.

4/25/2024

I took it to the dealer. They could not solve the problem. What would you recommend I do next? Do you know if there is another level of tech support at GMC?

Jesse M.

4/26/2024

@OttoB What is the year, make and model of this truck? Has it always been this way? Or is this an issue that arose recently? It is a bit odd that a GMC dealer could not address the issue, especially if this is a newer truck.

Otto B.

4/26/2024

@JesseM This has been the case since it was originally purchased in 2022. It is a 2023 GMC Sierra 2500 AT4HD. Apparently, the mechanic didn't have access to a protocol for this problem.

Jesse M.

4/26/2024

@OttoB The running light and tail light pins should not be hot all the time. Generally this issue is due to either a miswired trailer connecter, or a short in the wiring somewhere. Either way since the vehicle is so new this is definitely a GMC issue. You may have to hassle them into taking care of the issue because it sounds like the dealership you took it to would rather make excuses than address a problem that is clearly their responsibility. There has to be someone who can access the protocol somewhere. I would have to suggest you keep trying with GMC until they can get you in touch with someone who can help. The only potential solution we could offer would be to wire the vehicle with an aftermarket 7-way. This would get you a properly functioning 7-way, but it still would not resolve the issues with the OEM wiring.  

Otto B.

4/26/2024

@JesseM Thank you for taking the time to reply. I'll go back to the dealership and press to resolve.

Jesse M.

4/26/2024

@OttoB Good luck! Let me know if there is anything else I can do to help.

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