2013 Sprinter 2500 - 144”, high roof, crew edition, 136,187 miles. Diesel. Very frustrated Sprinter owner here...about 2,000 miles ago, I was faced with the DEF light/10 starts left situation. After exhausting all my options, I brought it to Mercedes. Turns out it was a bad DEF injection nozzle. They replaced that, and “updated my software” and it was over $1300. Yikes. Now here we are, roughly 2,500 miles later, and a check engine light comes on. No info on the small orange screen so it’s hard to say what it could be. The only parallels I can find right now, are that I was carrying probably 750lbs of gear in the back the first time the injection nozzle went bad. And yesterday, when the check engine light came on, I was carrying a similar amount of gear. Both times while traveling at highway speeds (~70mph). I remember my service advisor saying something about “when people come in to have work done, were programming things based on the current weight of the vehicle. Codes start to get thrown when people start adding more weight that the van isn’t used to....”or something along those lines. He also said that the replacement of the DEF injection nozzle was the first in line to likely solutions, and that in 500-800 miles, we’ll find out if other things went bad past the nozzle (i.e NOX sensors/catalytic converter). So, it makes me wonder, am I crazy for trying to find a correlation between weight here? Is there anything I can do to try and diagnose this myself? Really can’t imagine going and dropping another $1,000+ at Mercedes. As always, any help would be greatly appreciated.