I am new to DEF . We have 2018 Thomas saftyliner . I filled the tank today and the bars didn't light up to show it's full . We have had some cold temps in the low 30's . Not sure if that has anything to do with it . How easy is it to get to the sender if it is the seender ? What else could it be ?
I'm pretty sure the sender is not serviceable. You have to replace the entire unit. We haven't had any issues with Thomas' aftertreatment systems, but we have had problems with the Bluebird ones. I think they call them a DEF Multifunction Unit. It has the level, temp, and quality sensors all built into it.
it shows bars? float must be jammed seen it a couple times , if header unit or wire is bad it should log a code(short,open,blah,blah) DEF freezes at -11C and it usually takes 30 to 40 minutes for the coolant to thaw out completely
OEM trained in wiring and all engine platforms for over 20 years