Dodge Repair Questions? Ask a Mechanic for Answers ASAP
The dash gauge is part of the cluster and has no individual fuse.
The sending unit "trips" at 7 psi, then the instrument cluster - technical name Cab Compartment Node or CCN that is actually a computer made to look like the kind of thing we're used to - uses temperature and engine speed to make and display a calculated oil pressure.
Often times, disconnecting the truck main batteries will reset the CCN causing it to start working again. So, I would try that first (just make sure you have whatever codes you need for radio or any other accessory that require it). However, if the CCN still does not display a logical oil pressure value, then you might want to have it checked by a professional using a dealer-level scan tool.
I hope I've answered your question to your satisfaction. Please let me know if you need anything else.