If it's not the block heater cable for the cumins what else could it be? Maybe a holding tank heater pad?
Yes that plug is your block heater. Mine has an outlet on the back wall to the right of the inverter to plug it into. 750 watts from what I have read. Inverter is hard wired. Holding tank heaters are 12v and switch is located on the panel in the coach where the water pump & water heater switches are.
Excellent. Thank you. The dealer I purchased this rig from wasn't overly familiar with this model. I'm learning on the fly. Some challenges. Nice rig though. I may have more questions going forward. Thank to people like you I may enjoy the rest of the challenges.