My 2013 2609 CEL came on.

Checked the grid heater bolt and it was loose. I shut the truck down and removed it that day. 127K miles on the truck.

If you decide to keep it stock and replace with a new Cummins heater make sure you check the Torque on the inner bolt before installed.

The heater grid maintenance is required i think every 60.000 miles anyway for cleaning. Just replace it.

This took 2 days to get to me. I live in the North Pole it helps LOL.

https://www.ebay.com/itm/25427698447...m=254276984473