Mystery plug

[Helo Mech]

Just did my first oil change on my 2025 3500 Limited. Found this unused plug next to the oil filter. Anyone know what this is?

 

[wrvond]

block heater cable

 

[Helo Mech]

block heater cable

Thank you!

 

[Helo Mech]

Being that I took this option, shouldn’t this be connected to a harness that goes down to the bumper?

 

[Helo Mech]

Just did a little more digging. My harness is present all the way to the bumper. It looks like it is the block side that is disconnected. I will get back in there later and find it. Thanks again.

 

[wrvond]

Being that I took this option, shouldn’t this be connected to a harness that goes down to the bumper?

Yes, it should be connected to the heater. The heater is located near the oil filter and probably has a black plastic/rubber cap on it that just pops off. Plug the cable in and tighten the retainer ring and you're good to go.

 

[Helo Mech]

Yes, it should be connected to the heater. The heater is located near the oil filter and probably has a black plastic/rubber cap on it that just pops off. Plug the cable in and tighten the retainer ring and you're good to go.

Thanks for the help. Much appreciated.

 

[motorhead426]

block heater cable

Good thing you're working on it yourself. A tech at a shop probably wouldn't have noticed or mentioned it. I wonder what the out come would be if you plugged the bumper end into a 120v cord and had that open orange end just laying there? Hopefully not a fire. I will be checking mine after I pick it up. Thanks for sharing.

 

[Dodgeman]

Good thing you're working on it yourself. A tech at a shop probably wouldn't have noticed or mentioned it. I wonder what the out come would be if you plugged the bumper end into a 120v cord and had that open orange end just laying there? Hopefully not a fire. I will be checking mine after I pick it up. Thanks for sharing.

Nothing would have happened including block heating. It looks like the female contacts are well recessed so no fire risk. You would have been treated to a cold engine. However, the unconnected female end could become fouled with oily dirt. That should have been connected at the factory or by whoever added that.