No power on the trailer B+ charging wire 7 pin connector

Meldridge73 · July 1, 2023

I have a 2023 Silverado 3500HD High Country. A few days ago I went out to move my 5th wheel and found that I do not have any power at the 7 pin connector. I checked and changed the 30A fuse in the fuse box. I have a trailer wire tester that shows all other connections in the 7 pin are working (even the trailer breaks). I have two 7 pin connectors on the truck one in the bed and one on the bumper. Neither of these have the 12v+ power for charging. I am at my wits end with this thing. I am hoping that I can take care of this issue without taking it to the dealer but if not I will have to break down and take it in. Does anyone have any ideas on this issue?

64BAwagon · July 1, 2023

Did you check the panel to see if there was power to that fuse ?

If the batterys were down on the truck it may have disconnected power to that circuit.

According to the manual its fuse 63. Does everything else work on the truck ? I dont have the data but sometimes items are dependent on other circuits that arent obvious.

Meldridge73 · July 2, 2023

2 hours ago, 64BAwagon said:

Did you check the panel to see if there was power to that fuse ?

If the batterys were down on the truck it may have disconnected power to that circuit.

According to the manual its fuse 63. Does everything else work on the truck ? I dont have the data but sometimes items are dependent on other circuits that arent obvious.

I have not check to see if there is power to that fuse. I have not noticed anything else that isn’t working. I will check the power to that fuse tomorrow. I knew what fuse it was by the diagram in the panel and the manual. Thank you for your input. I will update once I check the power at the fuse.

Meldridge73 · July 2, 2023

19 hours ago, 64BAwagon said:

Did you check the panel to see if there was power to that fuse ?

If the batterys were down on the truck it may have disconnected power to that circuit.

According to the manual its fuse 63. Does everything else work on the truck ? I dont have the data but sometimes items are dependent on other circuits that arent obvious.

Update… I checked the voltage at the fuse. Meter reads 12.7v . I am going to start tracing the harness from the 7pin back to the fuse block today (weather permitting).

Edited July 2, 2023 by Meldridge73
Added picture of voltage at fuse.

64BAwagon · July 3, 2023

Check for continuity between the 12v+ on the plugs in the rear and the fuse.

I think all of the circuits on the trailer go through a control module towards the back. Its possible theres a malfunction there or a bad connection. Do you know for sure if that circuit has ever worked ? Its not unheard of to have connector issues where pins dont seat etc.

Meldridge73 · July 8, 2023

On 7/3/2023 at 8:59 AM, 64BAwagon said:

Check for continuity between the 12v+ on the plugs in the rear and the fuse.

I think all of the circuits on the trailer go through a control module towards the back. Its possible theres a malfunction there or a bad connection. Do you know for sure if that circuit has ever worked ? Its not unheard of to have connector issues where pins dont seat etc.

I know for a fact that it has worked. I have had my 5th wheel connected to it and it worked to operate the landing gear on a couple occasions. I have an appointment with the dealership Monday morning to have them look at it. Its frustrating when I have only had this truck less than three months.