P0606 code, but no MIL or other symptoms

[Thump]

Hi folks. I did a random key position code grab this evening just because and my 2011 3500 is showing a single code: P0606.
I have no MIL or any odd behaviors from the truck as have been described in other threads around here and in the wild.
Truck is bone stock with 120K on the ticker and has never been molested or hot rodded. This is te truck's first code, ever. So, I'm at a bit of a loss while also concerned about having a 4 ton paperweight. Any ideas or things you think I should try? I'very not yet invested in a scanner / DTC cleaning tool, so I can't just clear and see.
Thanks in advance

 

[sag2]

I would not give it a second thought. If it was a real code the CEL would also be on. Buy yourself a $100 scanner and keep from using the key thing.

 

[Thump]

Well, the code cleared for a bit.
Noticed that the tip to start was acting odd for several days and now... BAM! P0606 with MIL.
Just great
Anything to watch out for?