I know this topic cover a lot on here but I can’t find anything similar to my problem. I just replaced my DEF heater on my 2011 f250 because I got the P20BA CEL code. I stared it up and the code was gone. It did not return after I drove it about 40 miles. Now when I start the truck the CEL comes back on with the same code. I clear it and it does not return while driving but will come back as soon as I start it up again. Anyone have any thoughts? Thank you

 

I've got the same code for the second time. First time, I filled the def tank, then cleared the code. It held for about 2000 miles. Torque pro says I have 3.1 gallons of def, but I can't get it to take any more. Truck goes to the shop this afternoon.