Sierra 12v stays hot

[stephndudb]

Was surprised to discover that the 12v Battery line in the 7-pin trailer connector of our 2017 GMC Sierra 3500 stays hot even with the ignition off. On our old Ford there was a relay that cut power to the connector when the ignition was shut off. Will have to remember to unplug the trailer if we ever stop for the night and stay hitched.

[aeblank]

Originally Posted by stephndudb

Was surprised to discover that the 12v Battery line in the 7-pin trailer connector of our 2017 GMC Sierra 3500 stays hot even with the ignition off. On our old Ford there was a relay that cut power to the connector when the ignition was shut off. Will have to remember to unplug the trailer if we ever stop for the night and stay hitched.

True. GMs don't cut power.
You could add a relay.
I added a charge controller.