Cummins ISX15, fault code 0559 with fuel pressure issue. Could be the aftermarket injectors.

[@matthewhansen5008]

Can't recall if you said was this a 2250 or 2350 engine? Seeing how that fuel pump head looks to be original, might be worth the labor to pull fuel pump head and inspect plungers and rollers.

[@saluki417]

Typical x15 lol. Most of them are on recall now

[@normanjanan9189]

I have a 2016 Cascadia with a DT 12 transmission. My transmission stops working soon as I left the toll plaza with a no fault code and the screen has only show the symbol I’m - - _ The truck now is in the dealer. They can check on Monday. Any idea?

[@CarlosDieselElectric]

Possible CPC 4 is starting to fail. Try installing a test CPC4 from a similar truck. These have been know to fail with communication. Try testing first