GM Vehicles - trailer charge line not hooked up

[rotor_wash]

Pat, your profile doesn't list your TV, but if it is a late model GM product, the aux power wire may not be hooked up. This is where the TM gets it's power. I believe the 2007 year group was the first not to do this. The wires for both the trailer brake and aux power are taped down in the engine compartment near where they connect. This is of course requires your dealer to connect them even if you purchased the "trailer package". In reality, it is a very easy job that I did myself when I put in the Prodigy brake controller.
Additionally, if you ran the fridge on DC and the battery was not receiving a charge, you would quickly deplete it.